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FOOD INDUSTRIES 

An Elementary Text-book on the Produc- 
tion and Manufacture of Staple Foods 



DESIGNED FOR USE IN HIGH 
SCHOOLS AND COLLEGES 



by 



HERMANN T. VULTE, Ph.D., F.C.S. 

Assistant Professor Household Arts, Teachers College, Columbia University 



SADIE B. VANDERBILT, B.S. 

Instructor Household Arts, Teachers College, Columbia University 



E ASTON, PA.: 

THE CHEMICAL PUBLISHING CO. 

1914 



\X 3 53 



Copyright, 1914, by H. T. Vui/ris 



;£K 29 1914 



©CI.A380644 

- 



PREFACE. 

After many years' experience in lecturing on the processes of 
food manufacture, the authors feel encouraged to submit the 
result of their labors as a guide to those who wish to study this 
most important and interesting subject. 

Certainly no branch of general manufacturing has undergone 
so many and such important changes in the past twenty-five years 
as the food industries. The public have largely benefitted from 
these changes both in pocket and health. 

Unfortunately there still lingers in the minds of many, the 
impression that food stuffs have not the same dietetic value they 
possessed in the past, and that manipulation gives them an appear- 
ance of quality they do not possess. It is the universal experi- 
ence of the authors that manufacturers have not only improved 
the quality of their products in every possible way, but having 
nothing to conceal except from competitors, are most anxious to 
enlighten the interested consumer in the processes involved. 

Some mistakes have certainly been made in the past, but with 
no evil intent and largely through ignorance. As time passes 
these errors are corrected and it can confidently be stated that 
the public receives to-day better and cleaner material at a lower 
price than formerly. The economic improvement is largely due 
to the general utilization of by-products, many of which do not 
appear in any list of foods. 

The following pages do not claim to deal with any industry 
from the purely technical standpoint, but aim to point out the 
most essential parts of each. A knowledge of chemistry and 
physics is not absolutely essential, but is very helpful. 

As a pioneer book on the subject, any suggestions furnished 
by teachers would be very gratefully received. 

The authors are greatly indebted to Dr. H. C. Humphrey, 
Dr. W. D. Home, Dr. W. E. J. Kirk, Mr. George S. Ward and 
Mr. Earl D. Babst for valuable suggestions in regard to the 
subject matter of this book and to Mrs. Ellen B. McGowan of 
Teachers College for reading the manuscript. They wish also 
to acknowledge the assistance of the many manufacturers who 
have thrown their plants open for inspection and who have 
allowed the use of photographs and cuts of machinery. 
September, 1914. 



TABLE OF CONTENTS. 



PAGE 

Introduction 1-4 

Chapter I — Food Principles 5 -I 5 

Functions. Conservation of Energy. Elements in 
Foods. Food Principles. Examples of Each Group. 
Functions of Each Group. Importance of Water. 
Carbohydrates. Classification. Formation. Occur- 
rence. Important Properties. Hydrolysis. Fats. 
Composition. Occurrence. Properties. Solubility. • 
Change of State. Crystallization. Drying and Non- 
drying. Emulsification. Saponification. Proteins. 
Composition. Classification. Occurrence. Protein 
Hydrolysis. Properties. Solubility. Curdling. 
Coagulation. Clotting. 

Chapter II — Water 16-35 

Classification of Natural Waters. Water Supply. 
Historical. Classification of Potable Water. Atmos- > 
pheric. Surface Water. Subsoil Water. Pollution 
of Wells. Contamination of Public Supplies. Danger 
of Impure Water. Diseases from Water. Purifica- 
tion of Water. Public Methods. Bacterial Action. 
Filtration. Use of Chemical Agents. Household 
Methods. Boiling. Use of Domestic Filters. 
Manufacturers' Methods. Self-purification. Judg- 
ing a Water Supply. Ice Supply. Mineral Waters. 
Classification. Natural Mineral Springs. Occur- 
rence. Medicinal Power. Artificial Mineral Waters. 

Chapter III— The King of Cereals. Old Milling 

Processes 36-51 

Wheat. Origin. Geographical Distribution. Culti- 
vation. Structure of the Wheat Grain. Value of 
Wheat. Varieties. Old Milling Processes. Hand- 
stones. The Pestle and Mortar. The Quern. The 
Grist Mill. Disadvantages of Old Processes. 

Chapter IV — Modern Milling and Mill Products 52-65 

Dust Collectors. Fundamental Objects in Milling. 
Cleaning of the Wheat. Tempering. Separation of 
the Middlings. Reduction of the Middlings. Advan-- 



CONTENTS V 

PAGE 
tages of the New Process. Testing of Flour. Wheat 
Blends. Adulteration. Bleaching of Flour. Mill 
Products. Hard Wheat Flour. Soft Wheat Flour. 
Prepared Flour. Graham Flour. Entire Wheat 
Flour. Gluten Flour. Cereal Department. Seminola. 
Rye. Composition. Uses. Adulteration. 

Chapter V — Cereals 66-76 

Biological Origin. Kinds. Geographical Distribution. 
Use in Our Country. Indian Corn or Maize. Origin. 
Early Cultivation. Varieties. Early Methods of 
Preparation. Old Milling Methods. Samp. Hominy 
and Cornmeal. Modern Milling. Uses. Adultera- 
tion. Rice. Origin. Geographical Distribution. 
Composition. Cultivation. Milling. Adulteration. 
Uses. Oats. Composition. Oatmeal. Milling. 
Adulteration. Barley. Origin. Cultivation. Com- 
position. Uses. Mill Products. 

Chapter VI — Breakfast Foods and Coffee Substitutes. . 77-83 
Breakfast Foods. Classification. Uncooked. Partly 
Cooked. Cooked. Malted Preparations. Adultera- 
tion. Comparison of Old and New Cereals. Coffee 
Substitutes. 

Chapter VII — Utilization of Flour. Breadmaking. . . . 84-106 
Primitive Breadmaking. Leavened Bread. Flour. 
Water. Salt. Yeast. Leavening Effect of Yeast. 
Yeast Preparations. Home Brew. Brewer's Yeast. 
Compressed Yeast. Dried Yeast. Object in Bread- 
making. Steps in Breadmaking. Fermentation. 
Straight or Off'-Hand Dough. Ferment and Dough. 
Sponge and Dough. Baking. Cooling. A Modern 
Bread Factory. Souring and Its Prevention. Adul- 
teration. Losses in Fermentation. Chemical Process. 
Aerated Bread. Crackers. Macaroni. Manufactur- 
ing Processes. Domestic Macaroni. Judging Quality. 
As a Food. 

Chapter VIII — Leavening Agents 107-116 

Advantages of Yeast. Chemical Agents. Advan- 
tages. Disadvantages. Baking Powders. Tartrate 



VI CONTENTS 

Powder. Phosphate and Alum Powders. Compari- 
son of Tartrate, Phosphate and Alum Phosphate 
Powders. Relative Efficiency. Ammonia Powders. 
' Cream of Tartar. Tartaric Acid. Acid Phosphate 
of Lime. Bicarbonate of Soda. LeBlanc Method. 
Solvay Process. Niagara Process. 

Chapter IX — Starch and Allied Industries 1 17-129 

Starch. Composition and Formation. Physical 
Characteristics. Physical and Chemical Properties. 
Uses. Source of Supply. Potato Starch. Extrac- 
tion. Processes in Manufacture. Tapioca. Corn 
Products Industry. Processes in Manufacture. By- 
products and Their Uses. Dextrins. Uses. Corn 
Syrup or Glucose. Uses. Processes in Manufacture. 

Chapter X — The Sugar Industry. 130-152 

Source. History of the Sugar Cane. Histor}' of the 
Sugan Beet. Comparison of Cane and Beet Sugar. 
Properties of Sugar. The Cane Sugar Industry. 
Growth of the Cane. Production of Raw Cane 
Sugar. The Beet Sugar Industry. Beet Culture. 
Production of Raw Beet Sugar. Refining of Raw 
Sugar. Granulated Sugar. Block Sugar. Powdered 
Sugar. Utilization of the By-products. Yellow 
Sugar. Maple Sugar. The Date-palm. Sorghum. 
Cane Syrup. Adulteration of Sugar. 

Chapter XI — Alcoholic Beverages 153-164 

Classification. Historical. Fermentation. The Brew- 
ing of Beer. Raw Material. Processes in Manu- . 
facture. Composition of Beer. Adulteration. Sub- 
stitution. Kinds of Beer. 

Chapter XII — Alcoholic Beverages (Continued) 165-175 

The Wine Industry. Processes in the Manufacture 
of Still Wine. Improving Wines. Champagne. 
Sophisticated Wines. Adulteration. By-products. 
Distilled Liquors. Distillation. Bonded Whiskey. 
Cider. Vinegar. Adulteration. Koumiss. 

Chapter XIII— Fats „ 176-186 

Extraction. Purification. Butter. Composition. . 



CONTENTS Vll 

Processes in Butter-making. Renovated Butter. 
Oleomargarine. Material Used. Processes in Manu- 
facture. Olive Oil. Processes in Manufacture. 
Adulteration. Cottonseed Oil. Peanut Oil. 

Chapter XIV — Animal Foods 187-200 

Meat. The Physical Structure and Chemical Con- 
stitution. Meat Inspection. Reasons for Cooking 
Meat. Changes in Cooking. Beef Extracts. Beef 
Juices. Internal Organs. Fish. Nutritive Value. 
Edible Portion. Adulteration. Shellfish. Eggs. 
Physical Structure. Composition of the Shell. 
Methods of Preservation. Composition of the Egg. 

Chapter XV — The Packing House 201-209 

Historical. Growth and Breadth of the Industry. 
Processes in the Packing House. Inspection and 
Slaughtering. Use of By-products. Hides. Fat. . 
The Feet. Bone Products. Tankage. Blood. Mix- 
ing Fertilizers. Glue arid . Gelatin. Canning of 
Meat. Beef Extracts. Sausages. Minor Products. 

Chapter XVI— Milk 210-223 

Source. Composition. Importance of the Milk 
Supply. Diseases from Milk. Necessity for Clean- 
liness. Safeguarding the Milk Supply. Our Duty 
to the Producer. Testing of Milk. Sterilization. 
Pasteurization. Certified Milk. Modified Milk. 

Chapter XVII— Milk Products 224-234 

Condensed Milk. Evaporated Milk. Concentrated 
Milk. Milk Powders. By-products of the Butter 
Industry. Skim Milk. Dried Casein. Milk Sugar. 
Buttermilk. Artificially Soured Milk. Cheese. His- 
torical. Composition. Cheesemaking. Adulteration. 

Chapter XVIII — Preservation of Foods. . 235-246 

Classification. Drying. Cooling. Sterilization and 
Exclusion of Air. Sugaring. Salting. Smoking. 
Use of Fats and Oils. Use of Spices. Alcohol. 
Use of Preservatives. Artificial Sweetening. Arti- 
ficial Coloring. 



Vlll CONTENTS 

Chapter XIX — The Canning Industry 247-254 

Historical. Process. Success of Canning Fruits and 
Vegetables. Meat Products. Containers. Advan- 
tages and Disadvantages of Glass. Advantages and 
Disadvantages of Tin. Adulteration. 

Chapter XX — Tea, Coffee and Coco 255-276 

Historical. Cultivation of the Tea Plant. General 
Classification. Processes in Manufacture. Black 
Tea. Green Tea. Adulteration. Tea as a Beverage. 
General Rules for Tea-making. Composition of the 
Beverage. Coffee. Historical. The Coffee Plant. 
Cultivation. Processes in Manufacture. Adultera- 
tion. Coffee as a Beverage. Coffee Extracts. Coco. 
Historical. Cultivation. Processes in Manufacture. 
Preparation of Chocolate. Preparation of Coco. 
Adulteration. As a Beverage. 

Chapter XXI — Spices and Condiments 2JJ-2&J 

Salt. Spices. Uses. Spices as Preservatives. Vanilla. 

Pepper. Mustard. Cinnamon and Cassia. Cloves. 

Allspice. Nutmeg and Mace. Ginger. Adulteration. 

Vinegar. 

Bibliography 288-294 

Index 2 95- 



INTRODUCTION. 



In regard to the production and manufacture of our food 
material, there is a prevalent ignorance among woman to-day 
which is a marked contrast to the knowledge possessed on this 
subject by the old-fashioned housekeeper. The reason for this 
can readily be seen for in the early days, and in fact until com- 
paratively recent years, agriculture was very near the home and 
in the majority of cases the housewife herself was the manufac- 
turer. The spinning-wheel, now so highly prized as a memento 
of the olden times, testifies to the fact that our grandmothers 
knew full well how to manufacture the clothing for their fami- 
lies. A closer look at these same days will show that they knew 
equally well how to prepare many food products and materials 
needed for household work. 

As civilization has advanced the tendency toward the massing 
together of our population in towns and cities has gradually 
changed greatly the home life of the people. Agriculture no 
longer is carried on in proximity to the home, and large com- 
mercial establishments remote from the household now do the 
work that at one time was the daily duty of the housewife. 
Many such examples can be found. In our later study of the 
history of milling, we will find that among all primitive people, 
the woman was the miller, grinding each day the grain she was 
to make into bread; the preparation of the meal and breadmaking 
were practically one operation. Later on in the history of the 
human family, the making of meal and flour passed into the 
hands of the village miller, who ground the grain for the pro- 
ducers of his neighborhood, who in turn bought their sack of 
flour directly from him. As this business grew in size it grad- 
ually was moved further and further from the home, until the 
average housekeeper of to-day knows little of the mighty indus- 
try that is preparing the flour for her use. More and more each 
year, we find that the making of this flour into bread is in like 
manner passing into the hands of the modern manufacturer of 
bread. The old-time home-made loaf of bread is still found in 



2 FOOD INDUSTRIES 

isolated districts, but seldom in city life. In the preparation of 
alcoholic beverages we again find this marked change. As late 
as our own colonial days, every housewife knew how to prepare 
beer and wines and her reputation as a homekeeper was judged 
as much by the beer that she could brew, as by the loaf of bread 
that she could bake. The curing of meat and fish by salting and 
smoking, the drying of fruits and vegetables now are known only 
to the housekeeper in isolated sections of our country, for the 
city woman must depend on the manufacturer's supply. Even 
the preservation of our food by canning is rapidly passing into 
the hands of the canning industry. 

These marked changes in our food preparation have brought 
new types of foods on the market and have greatly increased the 
variety. To the modern housekeeper, they have brought both 
advantages and disadvantages. 

Advantages. — I. There has been a great lessening of household 
drudgery, giving an opportunity for broader interests and for 
more recreation than was known to our grandmothers. 

II. In the majority of cases better products can be obtained 
for the methods of preparation used by the housekeeper were 
necessarily very crude. Manufacturers for financial reasons must 
give much study to their particular industry and new and better 
methods are constantly being sought. This has led to improved 
sanitary conditions and a standardizing of the quality of the 
product. 

III. In recent years there has been a great extension of the 
open season ; fresh fruits and vegetables are now quite common 
in the city markets the year round. The variety of food has been 
also increased by canning. 

IV. Great improvements have taken place in the science of 
agriculture leading gradually to the raising not only of better 
products but to the increase in the area of production, of prod- 
ucts which formerly were obtainable only from a limited section, 
as oranges and other fruits, sugar from the beet and wines. 

V. New and improved methods of food preservation have been 
largelv studied as canning and the use of cold storage. 



FOOD INDUSTRIES 3 

VI. The co-operation with scientists has led to protection 
against certain diseases as tuberculosis from meat and milk, 
typhoid from the oyster, trachina from pork, etc. 

VII. Articles of food are now put up in better and more sani- 
tary packages and better packing material is being used. 

Disadvantages. — I. The cost of living has been greatly 
increased. 

a. Foods may be roughly divided into permanent and perish- 
able material. Among the permanent foods, the cost has de- 
creased, as sugar and flour. The great advance in price of our 
food material is found entirely in the perishable foods. Such 
material is now often brought from a long distance, thus adding 
cost of freight and many times the cost of preservation during 
transportation. The many hands through which food material 
must pass also increases the cost. 

b. Packages are sometimes used without enhancing the value. 
Many times this means that the actual weight of the food material 
is less than the housekeeper supposes as the weight of the box 
or package is included. 

c. The open market has led to expensive tastes. Luxuries look 
attractive and the cost is great where such products have been 
brought from a distance. 

II. The women of our country represent about 90 per cent, 
of the retail buyers in food products. A lack of knowledge and 
many times of interest have led to great deception on the part of 
some manufacturers. 

a. Until the Pure Food Law went into effect, there was a great 
amount of adulterated material put on the market and preserva- 
tives were most freely used. 

b. The substitution of cheaper products with intent to deceive 
the purchaser was also a common practice. Butter substitutes 
were sold as butter, cottonseed oil as olive oil, apple jelly as 
currant, canned herring as sardines, potted veal for chicken, and 
the like. 

c. Following these evils there gradually crept in the custom of 
printing misleading statements on the outside wrappers as to the 



4 FOOD INDUSTRIES 

effect and food value of the contents. Much advertising was 
done also giving these false impressions. 

Had the modern housekeeper possessed the knowledge of her 
grandmother as to the production and manufacture of food 
material she was buying, manufacturers would not have found 
it advantageous to practice such frauds for so long a period. 

The United States Government has for many years been study- 
ing and experimenting along these lines, and bulletins have been 
printed which can be procured free or at a very small cost, yet 
comparatively few housekeepers seek such information. This 
lack of knowledge and interest led the faculty of the School of 
Practical Arts, Columbia University, to introduce many years 
•ago, into its domestic science course, a study of the manufacture 
of food material, hoping that a more extended knowledge of this 
subject would lead to greater interest and more intelligent buying 
on the part of the modern housekeeper. 

In connection with the following course of lectures, excursions 
should be taken as frequently as possible to manufacturing estab- 
lishments, where processes and methods can be studied and sani- 
tary conditions noted. Wherever such excursions are not prac- 
tical, illustrative material and demonstrations should be most 
freely used, accompanied whenever possible by the use of the 
stereopticon and moving picture slides. 



CHAPTER I. 



FOOD PRINCIPLES. 

Food principles are types of chemical compounds differing in 
exact composition but of equal energy value. They are reducible 
to similar forms by the process of digestion. 

Functions. — Food has two important functions : first, to supply 
tissue for the growth of the young child, and since life's processes 
are continually breaking down this body structure, to supply 
needed material for its repair; second, to. furnish the organism 
with fuel which in burning gives power to carry on life's activi- 
ties ; the heat produced is utilized to maintain the temperature 
necessary to the organism. 

Conservation of Energy. — Locked up in the resources of nature 
is a vast wealth of energy. Man has only to seize this energy and 
convert it into a form which he needs. Thus we find wood, coal, 
petroleum and natural gas being utilized to give heat and light. 
Should the energy be contained in a compound which can be 
finally assimilated by the human body he can accept it as a food. 

Elements in Food. — Nature does not always give us these 
foods in a simple state ; many of them are quite complex in their 
nature. When analyzed, however, it has been found that even 
the complicated forms are composed of the most common ele- 
ments as carbon, hydrogen, oxygen, nitrogen, with a small amount 
of sulphur, phosphorus, iron, calcium, etc. 

Food Principles. — Although these elements may be differently 
combined, they can be divided into groups which are called the 
five food principles : 

i. Water composed of hydrogen and oxygen. 

2. Carbohydrates composed of carbon, hydrogen and oxygen. 

3. Fats composed of carbon, hydrogen and oxygen. 

4. Protein composed of carbon, hydrogen, oxygen, nitrogen, 

sulphur, generally phosphorus, sometimes iron, etc. 

5. Mineral matter — as sodium, potassium, calcium, magnesium, 

iron, sulphur, phosphorus, chlorine, and minute quanti- 
ties of iodine, fluorine and silicon. 



6 FOOD INDUSTRIES 

Examples of Each Group. — Among the carbohydrates we find 
such well-known foods as starch, sugar, cereals and vegetables. 
Fats may appear in different forms as liquids, semi-solids and 
solids, represented by olive oil, butter and suet. Protein in its 
most concentrated form occurs in the white of egg, large amounts 
being also found in meat, fish, cheese, eggs and milk. Usually 
we look to animal life for our protein supply, although it occurs 
also in the vegetable kingdom, relatively large amounts being 
found in beans, cottonseed meal, peas, lentils and smaller 
amounts in wheat, maize and other cereals. The vegetable king- 
dom supplies mankind with most of his carbohydrate food, 
animal carbohydrate occurring only in such forms as milk-sugar, 
glycogen and glucose. Fat occurs frequently in both animal and 
vegetable life. 

Function of Each Group. — Although all of the food principles 
have nutritive value each group has its own special function. 
This work may be : first, directly building tissue ; second, giving 
energy and heat; third, making it possible for other groups to 
carry out their special function. The great work of building 
tissue and gradually repairing it as it wears away can be per- 
formed by protein and inorganic matter, water always assisting 
in this work. The other food principles cannot build tissue; 
therefore, protein, mineral matter and water are absolutely essen- 
tial to life. None of the three is alone sufficient. The work of 
producing energy is done by all the food principles, although only 
in a very limited sense by mineral matter. 
Tissue Builders : 

Protein. 

Mineral matter. 

Water. 
Energy Producers : 

Protein. 

Carbohydrate. 

Fat. 

Protein alone is able to fulfil both of these functions of foods ; 
for this reason it is of vast importance in the diet. Without 



FOOD INDUSTRIES 7 

protein life is impossible for any length of time for the wear and 
tear on the tissue must be replaced. With protein assisted by- 
water life can be maintained for some time. In many classifica- 
tions only four food principles are given, protein, carbohydrate, 
fat and mineral matter, water being omitted. It is claimed that 
water cannot build tissue, neither does it supply the organism 
with fuel from which to produce heat and energy; therefore, it 
cannot be called a food principle. 

Importance of Water. — Whether this statement be true or not, 
tissue building and, in fact most of life's processes, cannot go on 
without the presence of water. Blood is the gr,eat carrier of the 
system and there water is essential. It acts as an eliminator, 
washing out the tissues and carrying away waste matter loitering 
there. Water acts as a chemical agent. It has the power, of dis- 
solving substances, is essential to hydrolysis and can, therefore, 
assist in bringing about such chemical changes that otherwise 
useless food can eventually become part of the living organism. 
Its services to all forms of life cannot be over-estimated. 
Whether we regard it as merely a chemical agent or as a true 
food, next to the atmosphere we breathe it is the most essential 
thing in life. 

CARBOHYDRATES. 

In order to obtain the necessary amount of heat, and muscular 
energy it is necessary to supply the body with fuel. This work 
is done largely by the carbohydrates, a group containing carbon, 
hydrogen and oxygen. The hydrogen and oxygen occur in the 
same proportion as in water, and the carbon as six or some mul- 
tiple of six in most of those forms utilized as human food. The 
carbohydrates owe their value as a fuel very largely to the carbon 
which on oxidation gives off much heat energy. They are found 
in a large variety of foods : flour, meal, cereals, sugar, starch, 
vegetables and fruits. Sometimes they appear in simple forms 
which can easily be made use of by the organism ; at other times 
so complicated is the. molecule, that only after many chemical 
changes do they assume a form simple enough to pass through 
the membrane of the intestines. From the standpoint of nutri- 
2 



b FOOD INDUSTRIES 

tion the alimentary canal must be looked upon as outside the 
body, the lining of this canal being the outer coating of the body 
proper. All foods, therefore, must be reduced to chemical com- 
pounds which are capable of passing through the walls of the 
intestines before assimilation. The most important properties 
for assimilation are solubility and osmotic power. Those carbo- 
hydrates which cannot be reduced to forms having these proper- 
ties cannot be utilized as food'. 

Classification. — 

I. Monosaccharids or Simple Sugars, C 6 H 12 6 . 

Glucose or grape sugar, formerly called dextrose. 
Fructose or fruit sugar, formerly called levulose. 
Galactose. 
II. Disaccharids or Double Sugars," C^H^O^. 
Sucrose or sugar. 
Maltose. 

Lactose or milk sugar. 
III. Po^saccharids or Complex Sugars, (C 6 H Irt 5 )„. 
Cellulose. 
Starch. 
Dextrin. 
Glycogen. 

Formation of Carbohydrates. — The monosaccharids or simple 
sugars are built up in the leaf of the plant, by the absorption of 
the carbon dioxide and water of the atmosphere. With the 
assistance of the chlorophyll cells of green plants and the energy 
of the sun's rays, the following compounds are formed in the 
leaf : 

H 2 + C0 2 — HCHO + 2 
6HCHO — C 6 H 12 O g 

Glucose, C 6 H 12 6 , is soluble and diffusible so it can pass from 
one part of the plant to another. When this material is to be 
stored as reserve food for the plant, water is withdrawn and 
starch, an insoluble and colloidal compound, is formed: 

*C 6 H 12 6 ^ (C.H 10 O B )» + H A 



FOOD INDUSTRIES 9 

Occurrence. — Glucose is an important simple sugar widely dis- 
tributed in nature, and is found to a great extent in the same 
plants as contain sucrose. Grapes contain about 20 per cent., 
hence the common name grape sugar. It occurs also in sweet 
corn and most of the garden vegetables and fruits. In animal 
life it occurs in small quantities in the blood, 0.1 per cent., where 
it is constantly being burned to produce energy. Where the body 
has more or less lost the power to burn glucose as with diabetes, 
it accumulates and is finally eliminated by the kidneys. 

Fructose is usually found associated with glucose. It occurs 
in the juices of sweet fruits, the largest amount being found in 
honey. 

Galactose is not found in nature. It occurs only in the splitting 
of lactose or milk-sugar during the process of digestion. 

Sucrose is the most important of the sugars as it is the 
ordinary crystallized sugar of commerce. It is found widely 
distributed in the vegetable kingdom in the fruit and juices of 
a variety of plants, many times occurring in relatively large 
amounts as in the pineapple, strawberry and carrot. It is ex- 
tracted commercially from the sugar cane, the sugar beet, the 
sorghum cane, the date palm and the sugar maple. 

Maltose never occurs in nature in large quantities. It is the 
carbohydrate which is formed from starch during the germina- 
tion of seeds. As a commercial product it plays an important 
part in the brewing industry, in the so-called malted breakfast 
foods and in malted milk. 

Lactose occurs in the milk of all mammals usually from 3 to 
7 per cent. It is the most abundant of the animal carbohydrates. 

Cellulose or crude fiber constitutes the framework of all vege- 
table tissue, so we find it widely distributed throughout the 
vegetable kingdom. It occurs in wood, linen, cotton, hemp, flax 
and paper. Much of our food as cereals, vegetables and fruit 
contain cellulose, but as it cannot be made soluble in the organism 
it has no food value. Other forms of life can utilize it, however, 
and we find it serving as food for insects and bacteria. 

Starch as it is found in nature is also insoluble and indiffusible, 



10 FOOD INDUSTRIES 

but here we find a carbohydrate which can be changed to a 
simpler form within the alimentary canal. It is found largely 
in vegetables where it is stored as food for the plant. 

Dextrin or, as it is commonly called gum, is formed from 
starch by the process of hydrolysis. In nature it occurs in ger- 
minating cereals. 

Glycogen is often spoken of as the animal starch, although it 
more closely resembles dextrin. It is found to the largest extent 
in shell-fish, especially the scallop. It is also abundant in the 
muscle and liver of both higher and lower animals, where it is 
stored and ultimately utilized as a source of muscular energy. 

Important Properties. — Among the most important properties 
of the carbohydrates are found solubility, diffusibility, hydrolysis, 
crystallization and action on polarized light. 

Hydrolysis. — This important property occurs repeatedly in the 
changing of complicated forms of food material, to such simple 
forms that they can be utilized by the organism. It has been 
defined by Alexander Smith 'as "A double decomposition involv- 
ing water" and by other well-known chemists as "A simplification 
with absorption of water." Changes taking place during hydroly- 
sis are always brought about by certain agents, which do not 
themselves enter in any way into the compound being formed. 
These agents may be heat, dilute acid, bacterial action, enzyme 
action, etc. The action always takes place in the presence of 
water, both the water molecule and the complex carbohydrate 
molecule breaking down to form a new carbohydrate molecule 
in which the hydrogen and oxygen appear in the proportion as 
in water. 



2 C 6 H 10 O 5 + 

Starch 


H 2 


^ 


'-'12-"-22^-'ll> 

Maltose 


C 12 H, 2 O n + H 2 
Maltose 


— 


2C 6 H 12 6 . 
Glucose 



Sucrose is a double sugar. When it breaks down under the 
influence of a catalytic agent it yields two simple sugars as 

C 12 H 22 O n + H 2 ^ C 6 H 12 6 glucose, 
C.H^CX fructose. 



FOOD INDUSTRIES II 

A special name lias been given to these two molecules, glucose 
and fructose. They are called invert sugar. This name has been 
given to them on account of their peculiar behavior toward 
polarized light. Before hydrolysis a sugar solution will rotate 
the plane of polarized light to the right, after hydrolysis to the 
left, hence the name invert sugar and the term inversion. 

Hydrolysis also occurs in the digestion of fats and proteins. 

FATS. 

Composition. — True fats are composed of the elements carbon, 
hydrogen and oxygen. Little was known of how these elements 
were combined in the formation of fats, until the investigation 
by Chevreul in the early part of the nineteenth century. He dis- 
covered that they were essentially salt-like bodies formed 
together with water by the combination of an acid and a base. 
With the exception of some of the waxes the base is always the 
same, the triatomic alcohol glycerine, C 3 H 5 (OH) 3 . The acid 
usually belongs to a series termed fatty acids and varies accord- 
ing to the fat. The three most common fatty acids are oleic, 
palmitic and stearic acid. Unless a fat or oil contains both 
glycerine and a fatty acid, it is not a true fat. 

C.H.COH), + 3 C 17 H 3:s COOH ^ C 3 H 5 (C 18 H 33 2 ) 3 + 3 H 2 0, 
Glycerine Oleic acid Olein Water 

C 3 H 5 (OH) 3 + 3 C 15 H 31 COOH ^ C 3 H 5 (C 16 H 31 2 ) 3 + 3 H 2 0, 
Glycerine Palmitic acid Palmitin Water 

C 3 H 5 (OH) 3 + 3 C 17 H 35 COOH ^ C 3 H 5 (C 18 H 35 Q 2 ) 3 + 3 H 2 0. 
Glycerine Stearic acid Stearin Water 

' Two or more of these fatty acids are generally present in all 
fats — mixed, not chemically combined. They differ in their 
physical nature. Olein is liquid at ordinary temperature and 
whenever this acid predominates, the fat appears in the liquid 
form as in olive oil. Palmitin is semi-solid; it predominates in 
butter and lard and is the largest part of the human fat. When- 
ever stearin is present in a relatively large amount, the fat is a 
solid as in suet and tallow. 

Occurrence. — Fats are found widely distributed throughout 
both the animal and vegetable kingdoms. In plants the percent- 



12 FOOD INDUSTRIES 

age varies to a great extent, approximately i per cent, being 
found in barley and 67 per cent, in Brazilian nuts. Fat usually 
occurs in inverse ratio to the starch. It is often difficult to 
extract as it is deposited throughout the plant; no part seems to 
be entirely wanting in fat. In animal life fats are present in all 
tissues and organs and in all fluids, with the exception of the 
normal urine. Large quantities are found in the abdominal 
cavity surrounding the kidneys, and beneath the skin of marine 
animals or those living in cold climates. Being present often in 
large quantities, it is very easy to extract. 

Properties. — The most important properties are solubility, 
change of state, crystallization, drying and non-drying, emulsifi- 
cation and saponification. 

Solubility. — Fats are soluble in gasolene, ether, chloroform, 
warm alcohol and carbon disulphide. These solvents may be 
used for cleansing purposes, for extraction and removal of grease 
stains. 

Change of State. — All fats have a definite melting point. They 
exist as liquids, semi-solids and solids according to the tempera- 
ture. This property is taken advantage of in the extraction of 
fats and as a means of identification. 

Crystallization.— All fats are highly crystalline. They form 
definite crystals and can be readily identified under a microscope. 
This has been of great value in detecting adulteration. 

Drying and Non-drying. — Certain oils are oxidized when 
exposed to the air and are converted into thick gummy masses. 
These drying oils when applied in thin layers on a surface form 
a dry, hard, transparent film. They are used extensively in 
paints and varnishes as linseed oil. Some oils such as cotton- 
seed possess this property to a limited extent, while others as 
olive oil show no sign of drying even when exposed to the air 
for an indefinite period. 

Emulsification. — Fats can be broken up in small globules by 
mechanical agitation. If these globules can be coated with a sub- 
stance which will prevent them from running together, they will 
remain in suspension. Egg albumin is very frequently the agent 



FOOD INDUSTRIES 



13 



used in making an emulsion ; example — mayonnaise dressing. 
This property is taken advantage of in soap-making and in the 
cleansing of fatty material by means of soap. It always occurs 
as an early stage in the digestion of fats. 

Saponification. — The process of splitting a fat into its con- 
stituents, fatty acid and glycerine, is termed saponification. It 
may be brought about by such agents as heat, mechanical agita- 
tion, bacterial action and use of an alkali. Saponification always 
occurs in the digestion of fats and in the process of soap-making. 



PROTEINS. 

Composition. — The proteins are very complex compounds 
differing greatly in composition and properties, but all are of 
high molecular weight. They are composed of carbon, hydrogen, 
oxygen, nitrogen, sulphur usually phosphorus, sometimes iron, 
lime, etc. As nitrogen compounds they play an important part 
in human nutrition, for they are essential to the growth of the 
living cells which make up the tissue. 

Classification. — The following is a modification of the classifi- 
cation recommended by the American Physiological Society and 
the American Society of Biological Chemists. 



{ Simple 



Proteins J Conjugated 



I Derived • • 



f Albumins 
Globulins 
Glutelins 
Alcohol solubles 
Albuminoids 

Nucleoprotein 
Phosphoprotein 



Primary . , 



^ Secondary 



f Coagulated proteins 
I Meta proteins 
! Protean s 

Proteoses 
Peptones 
[ Peptids 



Non-protein 



r Extractives 
-{ Amides 
I Amino-acids 



14 FOOD INDUSTRIES 

Occurrence. — Albumin is found in both plant and animal life. 
It occurs most abundantly in the white of egg, where it coagu- 
lates on being cooked in boiling water and becomes a hard white 
mass. It appears in milk as lact-albumin, in egg as ova-albumin, 
in fluids of the animal body such as muscle and blood as serum 
albumin. A small proportion of the protein of plant life occurs 
as albumin. 

Globulin is very similar to albumin, but differs from it in solu- 
bility. It occurs in both plant and animal life, but is far more 
abundant and wide-spread in plant tissue. Globulin is found in 
large proportion in hemp-seed, flax-seed, and in the seeds of the 
legumens. Animal globulin occurs in muscle and blood. 

Glutelins are nitrogenous compounds found in the cereal grains. 
The most familiar example is the glutenin of wheat. Alcohol 
solubles is a form of protein also found in cereals. The prin- 
cipal one is the gliadin of wheat. Glutenin and gliadin in the 
presence of water form the well-known substance gluten. 

Albuminoids occur in the skeleton of the body as the connec- 
tive tissue, bones, hair, nails, hoofs and horns. It is that form 
of protein which yields gelatin on cooking. 

Nucleo-proteins are complex proteins which are believed to be 
combinations of one or more protein molecules with nucleic acid. 
They are closely associated with the nuclei of cells in both plant 
and animal life and occur most abundantly in asparagus tips, 
the hearts of lettuce and internal organs such as liver, heart, 
kidney and pancreas. In the clearage of the molecule during 
digestion true nucleo-proteins are believed to yield uric acid. 

Phospho-proteins are proteins closely combined with mineral 
matter as phosphorus and sulphur. The most familiar examples 
are the caseinogen of milk and the vitellin of egg. 

Protein Hydrolysis. — As in the carbohydrates, protein must 
undergo hydrolysis or a simplification before such compounds 
can be assimilated by the body. This change involves a breaking 
down of the protein molecule, and the taking up of the elements 
of water, under the influence of agents such as heat, dilute acids 
or alkalis, bacterial action and enzyme action. The products 



FOOD INDUSTRIES 15 

formed are known as derived proteins. Primary derived pro- 
teins are those which have been only slightly modified, secondary 
derived forms those having been more completely acted upon by 
the hydrolytic agent. In this way are formed coagulated proteins, 
meta-proteins, proteoses, peptones and peptids. Peptones for a 
long period were believed to be the final product of enzyme action 
in digestion, but that action is now believed to be continued to 
the amino-acid. 

Extractives. — The name extractives has been given to a body 
of substances which can be extracted from meat by the action 
of cold water. The most important are creatin and creatinin. 
Although nitrogen compounds, they are not capable of building 
tissue and it is believed that they have little or no food value. 

Properties.- — Among the more important properties of the pro- 
teins are solubility, curdling, coagulation and clotting. 

Solubility. — Albumin is soluble in cold water; gelatin swells 
and all other proteins are insoluble. All proteins are soluble in 
dilute sodium chloride, and with the exception of albumin, all are 
insoluble in saturated sodium chloride. All proteins are insoluble 
in saturated solutions of ammonium sulphate. 

Curdling. — Curdling is a change which occurs in connection 
with conjugated proteins such as the caseinogen of milk. It is 
the precipitation of a soluble matter by means of an acid, without 
serious chemical change. 

Coagulation. — Albumins and globulins are made insoluble by 
heating to about 158 F. In concentrated solution such as the 
white of egg, solidification is caused throughout the mass. This 
is a chemical change always brought about by (1) heat some- 
times with the aid of dilute acid or (2) the action of alcohol. 

Clotting. — The term clotting is applied to conjugated proteins, 
when the molecule is split by means of an enzyme into two 
simpler proteins, for example, — caseinogen under the action of 
rennet is split into casein and para or pseudo-nuclein. 



CHAPTER II. 



WATER. 



In chemical language we speak of water as a compound con- 
taining the elements hydrogen and oxygen, in the proportion of 
2 to i by volume and i to 8 by weight. Such a compound, 
however, is never found in nature and the term as repeatedly 
used "pure water" is generally accepted, as meaning a water free 
from harmful ingredients and which can, therefore, be utilized 
for drinking and other household purposes ; contaminated or pol- 
luted water contains material injurious to health. 



Classification of Natural Waters. 

I. Atmospheric 



f Rain — Contains very little dissolved solids but dust 

and gases of the atmosphere. 
j Snow 
I Fog 



II. Terrestrial 



f Surface— Cloudy, usually a large amount of 
' suspended matter, minimum of dissolved. 
j Underground — Clear, minimum of suspended 
i matter, maximum of dissolved. 



[ Salt 



f Brines — Over 5 per cent, soluble salts. 

I Sea water — 3.6 per cent, solids. 

j Mineral — Excess of unusual mineral matter 

[ and gases. 

It is known as the universal solvent ; there is .scarcely a sub- 
stance existing which is not more or less soluble in water. Hard 
rock can be gradually worn away by its action, and glass, one of 
the hardest of known substances, will gradually dissolve. All 
natural waters are found, therefore, to contain foreign matter, 
gases and solid material of the atmosphere and earth, either 
dissolved or in suspension. Sometimes these materials occur in 
small amounts, at other times in relatively large proportions. 
The nature and amount of these gases and solids have a con- 
siderable influence on the effect of water to be used for household 
purposes. 

The two great uses for water in the household are for drink- 



FOOD INDUSTRIES 17 

ing and for cleansing purposes. There is a standard to estimate 
the purity of each. For detergent purposes, the amount of 
mineral matter present plays an important part, while for drink- 
ing, organic matter received directly or indirectly from sewage 
or industrial waste, constitutes the chief danger. A safe water 
supply should be reasonably free from objectionable mineral and 
organic matter. 

WATER SUPPLY. 

Historical. — Even in remote antiquity a high value seemed to 
have been placed on an abundant water supply, and a keen appre- 
ciation existed of the danger should such a supply become con- 
taminated. Settlements were made and communities grew near 
the source of available water, which many times was looked upon 
as a blessing bestowed by the gods. In districts where water was 
not abundant courses were constructed with much expenditure 
of time, money and labor to carry it from a distance where water 
was found to be pure and naturally plentiful. Such courses were 
built by the ancient Romans, where water could proceed by 
gravity from the distant mountains to the city where great reser- 
voirs were built for its storage. These reservoirs were still in 
use during the middle ages and the ruins to-day show how well 
they had been constructed. 

Methods of irrigation were used early in the history of the 
world, for reservoirs were known to have existed in Egypt 
before 2,000 B. C. They were utilized for the purpose of receiv- 
ing and storing the surplus water during the annual inundation 
of the Nile, the stored water being used for irrigation during 
seasons when the river failed to reach the crops. 

Pumping as it exists to-day was unknown among the ancients, 
but curious devices were constructed for the elevation of water, 
the ruins of which can still be seen in some parts of the Old 
World. One of the greatest curiosities of Zurich is the pump 
invented and erected by a tin-plate worker of that city. It con- 
sists of a hollow cylinder like a very large grindstone turning on 
a horizontal axis, and so constructed as to be partly plunged in a 
cistern of water. This cylinder is formed into a spiral canal by 



l8 FOOD INDUSTRIES 

a plate coiled up within it like the main-spring of a watch in 
its box. 

Bucket lifts in different forms seemed to have been employed 
the world over from 'the remotest historical times. In oriental 
countries an earthen pot attached to a rope wound around a 
windlass was used. Another form was the scoop-wheel composed 
of a series of curved blades, terminating in a hollow axle into 
which they discharged the water scooped up by the revolution 
of the wheel. A series of buckets was sometimes arranged 
around a huge wheel which in revolving scooped up the water. 
The well sweep or bucket and balanced pole, still frequently seen 
in certain rural sections of America, were water elevators of the 
same simple construction and principle. 

The displacement pump acting on the principle that two bodies 
cannot occupy the same space at the same time finally took the 
place of the bucket lifts, and in the sixteenth century we find 
pumps being introduced into Germany and France. A little later 
than this Paris constructed a filtering plant. Methods of puri- 
fication, however, had been studied much earlier for we read that 
400 years before the Christian Era, Hippocrates had advised 
boiling and filtering drinking water should the supply become 
contaminated. 

Classification of Potable Waters. — 

I. Atmospheric. 

II. Surface. 

f shallow, 
III. Sub-soilj dee 

I. Atmospheric. — Rain is the original source of all natural 
water. It results from the water-vapor rising from the earth, 
being condensed in the upper air and again falling to earth. In 
its descent it to a great extent purifies the atmosphere by taking 
up ammonia, carbon dioxide and other soluble gases and by 
washing down solid matter as dust, soot, industrial waste and 
disease germs. Near the seacoast, rain water is found to contain 
an appreciable amount of salt dissolved in it. In districts con- 
taining a number of inhabitants and factories rain water is never 



FOOD INDUSTRIES 19 

pure, for even after prolonged washing the atmosphere is still 
more or less impure. This is not true in the open country for 
there after the air has been purified by the first rain that falls, 
the water can be collected and stored. This is the purest form 
of natural water known. 

Stored rain should only be used where natural water cannot 
be obtained pure enough for household purposes. In collecting 
rain the first flow should run to waste, thus avoiding contamina- 
tion by dirt, soot and other impurities washed from the atmos- 
phere and from the surface on which the water is collected. 
Such water should be filtered and great care should be given to 
the storage. Cisterns should be so constructed that they will be 
absolutely impervious to surface drainage, and so that they can 
easily be inspected and frequently cleaned. The best materials 
for building are brick, stone, cement and slate. They should be 
kept covered to prevent impurities from falling in and to exclude 
light. This will prevent the development of low forms of plant 
life. 

II. Surface Water. — After reaching the earth a portion of rain 
water runs over the ground to join streams or larger bodies of 
water. Of these waters lakes and rivers form an important 
source of our water supply. They are known as surface waters. 
The composition varies greatly according to the character of 
the soil over which they flow. Should the soil be rocky a por- 
tion of the mineral salts would undoubtedly be added to the 
water, but it would be more or less free from organic impurities. 
If the water comes in contact with swampy land it will be very 
rich in organic matter. The character of these waters varies 
also according to the uninhabited or settled condition of the 
locality. Water from a clear lake or river, exposed to the sun- 
light and air, is one of the safest of water supplies in a thinly 
populated region. Such bodies of water, however, become highly 
polluted should they receive the drainage of city or town life. 
From every point of view running streams should be kept free 
from organic matter if they are to be used as a water supply. 

III. Subsoil Water.— The portion of rain water which sinks 



20 FOOD INDUSTRIES 

into the ground is known as subsoil or ground water. It is used 
as spring water and shallow or deep well water. Subsoil water 
is greatly changed by the character of the earth through which 
it percolates. It passes to various depths according to the 
porosity of the soil and the arrangement of the strata. When it 
reaches an impervious formation it accumulates upon the level. 
In its descent to the earth and again in the soil, water dissolves 
more or less carbon dioxide. The presence of this gas greatly 
assists in dissolving mineral constituents of the soil. Thus we 
find in limestone regions a large amount of calcium carbonate in 
the water supply, making the so-called hard water. This greatly 
influences water to be used for detergent purposes. Rain water 
percolating through the ground may be changed also in regard 
to its purity as a drinking water. As it enters the soil it carries 
with it whatever organic matter it has dissolved from, the atmos- 
phere. In the upper layer, it again dissolves organic ingredients 
and becomes impregnated with micro-organisms, through the 
agency of which the organic matter undergoes very important 
chemical changes, gradually bringing about the purification of 
the water. Water which has percolated through the earth makes 
a very safe drinking supply, unless there is special contamination 
due to admixture with sewer drainage which contains excretory 
products. 

Shallow wells are much more likely to be subject to pollution 
of this kind. As a rule deep wells, 700 feet or more, are not apt 
to be dangerous, but they are usually higher in mineral sub- 
stances than surface waters. 

Pollution of Wells. — The chief danger to the water supply 
comes from earth closets, cesspools and house-drainages. To 
avoid expense in construction, too often the well and cesspool 
are built comparatively near together. The bottoms and sides 
of the old-fashioned cesspool were usually left open; to allow the 
house sewage to drain into the surrounding soil. Such condi- 
tions are a great source of danger and it is hoped that the septic 
cesspool will be more universally constructed in the future. In 
the septic cesspool, purification takes place by bacterial action and 



FOOD INDUSTRIES 21 

the water is not allowed to drain from it until it has been more 
or less freed from dangerous material. As regards location it is 
a common belief, that if the well is built on slightly higher ground 
than the earth closet or open cesspool there can be no danger of 
pollution. This is a false impression, however, for it is not so 
much the location that determines the possibility of pollution, as 
the relative position of the cesspool and the point where the 
water enters the well. Great carelessness has very often been 
shown in this direction by the property owner, who has little 
regard for the rights of his neighbors unless compelled by legal 
restrictions. His own water supply may be carefully guarded, 
but the cesspool may be so located as to be a serious source of 
danger to neighboring wells. 

Contamination of Public Supplies. — Much trouble has been 
caused in the past by the same carelessness in regard to larger 
supplies, that is, the location of earth closets and cesspools along 
the watershed of a public water course. This utter disregard of 
the rights of others has been practiced by communities as well 
as individuals. The municipal supply furnished to the larger 
cities and towns is often drawn from great bodies of surface 
water, as lakes and rivers. Here there is great opportunity for 
gross neglect of sanitary conditions. Steamships and sailing 
vessels make a practice- of discharging their waste matter into 
the water. Manufacturing establishments along the banks add 
to the pollution. The greatest danger, however, comes from 
looking upon rivers as a convenient receptacle for the disposal 
of sewage, for as it has often been said by Mrs. Richards, "It is 
only after contamination with the waste of human life that 
danger comes to other beings." Many epidemics of typhoid in 
the New World and of cholera in the Old World have been 
caused by using the same body of water, as a water supply and 
as a means of disposing of refuse. One town may take its 
water from a point above and discharge its sewage at another 
point below, a second town farther down the river takes the 
already contaminated water for drinking purposes, and in its 
turn discharges the sewage at another convenient point. 



22 FOOD INDUSTRIES 

Danger of Impure Water.- — Hutchison in his "Foods and 
Dietetics" tells us that water is not absorbed by the mucous 
membrane of the stomach ; it begins to flow into the intestines 
at once. The rapidity with which water passes through the 
stomach causes it to be a very dangerous vehicle of infection, 
for the hydrochloric acid of the gastric juice has not the oppor- 
tunity to act upon any disease bacteria which it may contain. 
Once in the intestines pathogenic bacteria find an alkaline medium 
which is most favorable for their growth and reproduction. For 
this reason it is quoted that "Contaminated water is a more 
obnoxious carrier of disease than impure milk." Too much care 
cannot be given that our water supply be above suspicion. 

While it is the duty of a city or town to supply a safe drinking 
water, to properly construct and maintain reservoirs and filter- 
ing plants, and to provide police surveillance for the water shed, 
it is also the duty of every citizen in such a community to cheer- 
fully pay the necessary expense for its maintenance, and to guard 
his neighbors' rights as his own. Education of the people at 
large on this subject is one of the essentials of modern life. 

Diseases from Water. — The presence of mineral matter quite 
frequently causes temporary intestinal derangement. This is 
more apt to be true with the visiting stranger to a community 
than with those accustomed to its use. The change from a soft 
to a hard water disturbs digestion and frequently causes con- 
stipation, while the change from a hard to a soft water may 
bring about diarrhoea. Organic pollution from vegetable origin 
has also been the cause of many mild epidemics of diarrhceal 
troubles. It is, however, to the typhoid and cholera bacteria that 
the world has owed its death destroying epidemics. 

Cholera has its home in India and has been largely kept alive 
and scattered in all directions, by the pilgrimages taken to such 
sacred rivers as the Ganges. The pilgrims from all parts of 
India travel in large companies for hundreds and even thousands 
of miles. Exhausted, filthy and many times diseased at the end 
of their journey, it is their custom to bathe in and drink of the 
sacred waters. Poorly fed and sheltered in the midst, of the 



FOOD INDUSTRIES 



23 



most insanitary conditions, it is little wonder that a cholera 
epidemic is soon started and by returning pilgrims is carried to 
all parts of the country. The European and American nations 
hear with horror tales told of cholera in India, and yet although 
more enlightened and understanding more fully sanitary condi- 
tions, Europe and America have repeatedly been visited with 
typhoid epidemics. It has been said that we have not advanced 
far in civilization, when we have not yet learned as a nation to 
take care of the excreta from our own bodies. Not until the 
end of the nineteenth century were authorities fully awakened to 
this subject, and there is still much work to be done in this 
direction. 

PURIFICATION OF WATER. 

Public Methods. — With the constant increase in our population 
and the modern tendency toward city and town life, a pure water 




Fig. 1. — Sedimentation Basin. 

supply has become almost an impossibility. The most that we can 
demand now is a safe water. Large sums of money have been 
used and much experimentation has been carried on of late years 
to determine the best methods of purification. Several very effi- 
3 



24 



FOOD INDUSTRIES 



cient methods have been discovered and are now in use, but 
which is best seems to depend on local conditions. The most 
important public methods are bacterial action, filtration and the 
use of chemical agents. 

Bacterial Action. — This method is used largely in England and 
is commonly spoken of as the English Filtering System. It con- 




Fig 2— Section of an English Filter Bed. (Courtesy of John Wiley & Sons.) 

sists of a filtration through sand-beds which are filled with putre- 
factive bacteria. Water to be filtered is usually run into a sedi- 
mentation basin first, in order to allow suspended matter to 
settle (Fig. i). This will prevent a too rapid clogging of the 
filtering beds if the water is materially turbid. After sedimen- 
tation has taken place, the water is delivered into the top of the 



FOOD INDUSTRIES 



25 




26 FOOD INDUSTRIES 

beds which are built of stone or concrete and have drainage pipes 
at the bottom, to discharge the filtered water into wells. In the 
beds are placed from the bottom upward layers of coarse gravel, 
fine gravel, coarse sand and fine sand (Fig. 2). The water 
percolates through the layers of sand and gravel to the drainage 
pipes which carry it away to the reservoir. Soon a slimy growth 
containing bacteria occurs on top of the filter beds ; these bacteria 
are the true purifying agents. For a long period after this 
system was put in operation, the purification was supposed to be 
entirely mechanical, then it was thought to be due to oxidation. 
It was discovered eventually that the filter beds failed to work 
thoroughly until the layer of slime had formed, and after much 
experimentation the purification was traced to bacterial action. 
The slimy mass acts as a mechanical agent, and through its bac- 
teria causes the oxidation of organic matter and destruction of 
pathogenic bacteria. When the sediment layer becomes so dense 
that the required amount of water fails to pass through, it 
becomes necessary to clean the bed by the removal of the top 
layer (Fig. 3). The scraped-off sand can be washed by a machine 
and stored for future use. Several days are required for the 
formation of a new sediment layer before the filter bed once 
more becomes effective. 

Filtration. — A system much in use called "The American Filter 
System" depends on the use of alum and filtration through sand. 
As in the English System the water to be filtered is first run into 
a sedimentation basin, after which potash alum or aluminium 
sulphate is added, 1/10 to 1 grain per gallon. The water is then 
admitted to a filter which is cylindrical in shape, made of wood 
or iron and is filled three-quarters full of fine sand (Fig. 4). 
Alum will readily ionize in water forming a heavy white floccu- 
lent precipitate of aluminium hydrate, jelly-like in appearance. 
K 2 A1 2 (SCU + 3 H 2 -> Al 2 (OH) 6 + K 2 SO, + 3H 2 S0 4 . 

The precipitate collects on the top of the sand as the water 
filters through. The action of this mass closely resembles the 
clarifying of coffee with egg albumin. It entangles all suspended 
matter which may be purely inorganic or living organisms and 



FOOD INDUSTRIES 



27 



deposits them on the surface of the sand. The jelly-like layer 
then acts mechanically much as the bacterial layer of the English 
filter-beds. 

Use of Chemical Agents. — Chemical treatment has been long 
used as a means of purifying water and has been found very 
efficient in periods of epidemics. Permanganate of potassium 
has been used in India during cholera epidemics. This acts as an 




Fig. 4. — View of the Interior of the East Albany, N. Y., Filter-plant. 
(Courtesy of John Wiley & Sons.) 



oxidizer of the organic matter in water and then attacks the 
bacteria. Sodium hypochlorite, chlorine and bromine are also 
effective in destroying micro-organisms. Perhaps alum is the 
agent most commonly employed for purifying water. It was 
first used in Egypt during the time of Napoleon to clarify the 
muddy water used by his army. As it has been previously 
described, alum will form a precipitate carrying down all sus- 
pended matter and will greatly improve the appearance of water. 



28 FOOD INDUSTRIES 

This method of purification is used quite extensively in public 
baths. For drinking purposes it should only be used in small 
amounts. Where alum has been used to throw down coagulated 
matter, it increases the hardness of a naturally hard water. In 
order to overcome this hardness, sodium carbonate is added in 
amount calculated to precipitate all as carbonate of lime. 

Household Methods. — Where public methods cannot be depended 
upon or in times of special contamination, it is often necessary 
for the householder to purify his water supply. The most 
common methods are boiling and the use of domestic filters. 

Boiling.— Boiling is the oldest and simplest way of purifying 
water. It has been used from the earliest times and is still one 
of the most effective methods that we have. As the chief danger 
of a polluted water comes from the typhoid bacillus, whose 
thermal death point is below the boiling point of water, prolonged 
boiling is not necessary. Boiled water is not palatable as the air 
has been driven out. It is well to cool and pass it from one 
vessel to another or to agitate it in contact with the air to restore 
the original taste. 

Use of Domestic Filters. — Most of the many varieties of house 
filters remove only dirt, iron rust and other coarse particles in 
suspension. They are usually small in size and contain a com- 
paratively small amount of sand or charcoal. While sand is 
effective on a large scale and charcoal is a well-known deodorizer 
and clarifier, the amount is not enough to affect a large quantity 
of water run through them, with the pressure of the ordinary 
city supply. In a very short time these filters become impreg- 
nated with bacterial life, the growth and development of which 
soon make them a dangerous medium through which to pass 
water. Effective filters, however, can be bought, but at a much 
higher price than the ordinary house filter. The Berkefeld 
(Fig. 5), Pasteur-Chamberland and Aqua Pura are filters of this 
type. The filtering medium in the first two is unglazed, well- 
baked porcelain, and in the latter, sandstone. Both of these 
media are capable of holding back micro-organisms as well as 
suspended matter. Great care must be given these filters to have 



FOOD INDUSTRIES 



2 9 



them work effectively. Bacteria soon cover the filtering surface 
and must be cleaned off by scraping or scrubbing. Most filters 
of this type also require sterilization by baking, boiling or sub- 




Fig. 5.— The Berkefeld Filter. 

jecting them to live steam. Unless the housekeeper is willing to 

give the filter proper care it is far safer to simply boil the water. 

Manufacturers' Method. — Boiling on a large scale has been 




Fig. 6.— Distillation Apparatus. (Courtesy of Carl H. Schultz Co.) 



30 FOOD INDUSTRIES 

found so troublesome, that most manufacturers who must purify 
water before Using it prefer the method of distillation (Fig. 6). 
Here water is raised to the boiling point, passes off as steam to 
another receptacle where it is condensed. This produces a sterile 
water as bacteria do not pass over in the distillate. It, however, 
is tasteless and needs aeration. 

Self-purification. — In the examination of surface waters, it has 
frequently been found that water taken from a river at a given 
point contains a certain amount of impurities ; at another point 
farther down there is considerably less, while at a still greater 
distance it is practically pure. This is supposed to be due to the 
fact that water can in time bring about its own purification. It 
is accounted for in several ways : first, the water becomes diluted ; 
second, changes take place due to oxidation and bacterial action; 
third, sedimentation; fourth, purifying influence of algae and 
other low forms of vegetable life. 

Could these agents always be relied upon there would be no 
need of constructing and maintaining expensive filtration plants. 
Undoubtedly they produce great results in many cases, but at 
other times the purification is only partial while at times it is of 
no special value. There is great danger, therefore, in relying on 
water to purify itself. Conditions might exist or arise which 
would prevent these agents from doing their work. Where self- 
purification is used, every precaution should be taken by the 
local authorities to guard the entire water-shed from all possible 
contamination. 

Judging a Water Supply. — In regard to a drinking water the 
world at large still retains the primitive idea, that purity in 
appearance alone is necessary in judging a safe water. Expert 
examination has shown that appearance alone is of little value. 
A pure water is generally bright and sparkling, but it has been 
found that some highly contaminated waters show remarkable 
brilliancy. On the other hand water may be distinctly muddy, 
owing to minute particles of clay or turbid from the effect of 
iron, and still not be dangerous. Neither can safety be judged by 
color and odor. Color may be due to traces of iron or to leaves 



FOOD INDUSTRIES 3 1 

and other such color imparting substances. The presence of color 
does not indicate that water is unfit for domestic use, neither 
does the absence of color indicate purity, for many polluted 
waters are colorless. Repulsive odors in water usually mean 
stagnation, presence of dead animals or other decomposing organic 
matter which makes it unfit for drinking purposes, but many 
odors may be present in water which are perfectly harmless as 
grassy or peaty odors. The only safe way of judging the purity 
of a water supply is by chemical and bacterial tests. The chem- 
ical examination usually made is for the presence of organic 
matter, and consists of the quantitative examination for the total 
solids, free ammonia, albuminoid ammonia, nitrites, chlorides 
and oxygen consuming power. Such tests to be reliable should 
not be made by the amateur, but by an expert chemist in a room 
set apart for this purpose. 

Great care should be given in collecting a sample of water to 
be sent for examination, since careless, handling would make the 
analysis worthless. If the bottles have not been provided by the 
chemist, a glass bottle or a demijohn which has been thoroughly 
cleaned and fitted with a glass stopper or new cork can be used. 
Details in regard to further directions for collecting samples, the 
significance of the tests and analytical methods can be found in 
"Air, Water and Food" by Richards and Woodman or other 
standard works on water analysis. 

Ice Supply. — The taking of ice from polluted waters has been 
a subject much discussed of late years. Many micro-organisms 
including typhoid are not killed by freezing, and it is claimed by 
many scientists that such ice is dangerous if put into drinking 
water for cooling purposes. It is a well-known fact that cold 
storage food will deteriorate rapidly when taken from ice. This 
would not be true if bacterial life had been destroyed. It has 
been discovered, however, that after prolonged freezing most 
germs are practically harmless, and for that reason some scien- 
tists claim that ice is safe to use even if taken from a con- 
taminated water. If there is any doubt of the ice supply, it is 



2,2 FOOD INDUSTRIES 

far safer to chill drinking water by placing it in bottles on ice, 
rather than by putting the ice directly into the water. 

MINERAL WATERS. 

The term mineral water is usually applied to spring water 
which contains a larger volume of gases dissolved in it, or more 
solid matter in solution than ordinary drinking water. It may, 
therefore, exert a different effect on the human body. 
Classification. — Acidulous. 

Alkaline. 

Bitter. 

Sulphur. 

Chalybeate. 

Acid. 

Alum. 

Borax. 

Saline. 

Lithia. 
These mineral waters may be either natural or artificial. 

Natural Mineral Springs. — Mineral springs have been found in 
many countries of both the Old and New World, and from the 
early ages have attracted much attention. They often present 
remarkable appearances when relieved from subterranean pres- 
sure by losing their gases with great rapidity. This often causes 
them to be thrown upward to a height of 20-40 feet* accompanied 
by a hissing or rumbling noise. Some waters are icy cold while 
others are at a boiling heat. These and other phenomena led to 
many superstitious beliefs in the early ages, and these waters 
were supposed to possess supernatural properties. There is, 
however, nothing unnatural about their origin. Subsoil water 
containing a considerable amount of carbon dioxide may sink to 
great depths, and may be subjected to great pressure or even 
heat. Should such water find an outlet it would tend to escape 
with considerable force. Much of the dissolved matter undoubt- 
edly is obtained from rocky soil through which the water has 
percolated. The solvent action of water, greatly increased by 



FOOD INDUSTRIES 33 

the presence of carbon dioxide and sometimes heat, may take 
from one type of rock certain acids which later react with basic 
elements dissolved from another rock, thus producing salts. Salts 
of lime, magnesium and iron are quite frequently found in these 
waters. 

Occurrence. — Mineral springs have been found to occur most 
frequently in volcanic districts where there is much carbon 
dioxide and many mineral compounds. They also occur in many 
other parts of the world and there are but few countries where 
they have not been found. France, Germany, Italy, Spain, 
Greece, Asia Minor, United States, and Canada are rich in min- 
eral springs, while they can also be found in Great Britain, 
Sweden, Norway and in many parts of Africa and the Orient. 

Medicinal Pozver. — Mineral waters have been used as medic- 
inal agents from very early periods. The pages of ancient 
authors frequently contain wonderful tales of their curative 
power, and records speak of resorts where the sick bathed in 
healing waters or drank of medicinal fountains. These mineral 
springs seemed to have played an important part in the religion 
of some nations, for the Greeks frequently erected their temples 
near such places, where their gods could be worshiped and their 
sick healed of whatsoever disease they had. In the pages of 
Latin writers we meet often with allusions to medicinal springs, 
and the splendor of the buildings erected in their vicinity in 
Italy testify to the esteem in which they were held by the 
Romans. This faith in the curative power has come down from 
these early times to the present day. How much they do really 
affect disease is a question of much interest to the modern phy- 
sician. Great difficulty is experienced by investigators of the 
subject for it is hard to eliminate other circumstances which con- 
tribute to the cure of the patient. A different climate, possibly 
a change in altitude alone has a remarkable effect in many dis- 
eases. Different diet, complete rest, change in hours of going to 
bed and getting up, new and possibly cheerful society, relief from 
the harassing cares of business or demands of social life are 
obtained. Patients after a short period at these springs return 



34 



FOOD INDUSTRIES 



to their homes much improved, many times entirely due to rest, 
recreation, more open-air exercise, regular habits, etc. It is 
hardly fair, however, to state that the waters have had no part 

Carbonic Acid Gas 
Generator. 




Fig. 7- — Carbon Dioxide Generator. By allowing sulphuric acid to flow drop by drop" |J 
from the upper container into the lower tank which is filled with, a solution of 
bicarbonate of soda, carbon dioxide gas is obtained. (Courtesy of Carl H. Schultz 
Co.) 

in the benefits obtained. The feeling against these mineral 
springs or spas as they are frequently called has come largely 
from the quackery surrounding the resorts. The superstition of 



FOOD INDUSTRIES 35 

past ages gave to them the power of curing all diseases. This 
same "cure-all" style of advertisement is still largely used by 
proprietors of springs and local physicians in the hope of attract- 
ing large crowds, and has done much to bring odium on the spas 
and to disgust the modern scientist. Before taking these waters 
care should be given that the water is effective for the specific 
disease, and that sanitary conditions surrounding the springs have 
been carefully guarded. There is no reason to believe that min- 
eral water will not become as highly contaminated as ordinary 
drinking water if exposed to sewage. It has long been a custom 
also to bottle and sell mineral waters, and should they be con- 
taminated, disease can readily be carried to all parts of the 
country. 

Artificial Mineral Waters. — In the latter part of the eighteenth 
century, Joseph Priestly suggested that an artificial aerated water 
could be made by charging water with carbon dioxide. The gas 
was obtained by the action of oil of vitriol on chalk. 
H 2 SO, -f CaC0 3 ~- C0 2 + H 2 + CaSO,. 

This carbonated water is still largely used, but most manufac- 
turers at the present time prefer to use bicarbonate of soda as a 
means of generating the gas, as the soda compound being soluble 
is less troublesome (Fig. 7). 

H 2 SO + + 2NaHC0 3 — 2C0 2 + 2H 2 + Na 2 S0 4 . 

From this simple suggestion of Priestly has grown an industry 
for making not only carbonated water, but mineral waters closely 
resembling the natural mineral springs. By careful analysis of 
the spas, chemists have been able to combine mineral salts in the 
same proportions, thus giving an artificial water claimed by 
many to be as beneficial as the natural water. Care should be 
given, however, in the use of these waters that the firm placing 
them on the market is thoroughly reliable. 



CHAPTER III. 



THE KING OF CEREALS. OLD MILLING PROCESSES. 

Taking the civilized world as a whole, both in the quantity 
produced and in its value as a human food, wheat has won the 
name of the world's King of Cereals. It is the cereal best 
adapted for bread-making and appears to meet the needs of 
civilized life more than the other grain foods. As the standard 
of living advances in a nation, wheat has grown steadily in com- 
mercial importance. 

If there were time to look thoroughly into the history of this 
cereal, we should find that the growth and development of wheat 
has been interwoven with the very life history of the human race. 
Origin. — It is impossible to tell how long it has been utilized 
as a food by mankind, for archaeologists claim that its record 
began in prehistoric times. The most ancient languages mention 
it and the fact that it has been found in the earliest habitations 
of man is a proof of its antiquity.' Specimens have been dis- 
covered in the Swiss lake dwellings and among the remains of 
Egyptian civilization. The Chinese claim that it was grown in 
their Empire over 3,000 years before the Christian Era and the 
Bible mentions its use as early as the Book of Genesis. If these 
accounts be true, wheat must have kept its place in man's diet 
for nearly 6,000 years. Such a record of long, faithful service 
could not be unless the grain of wheat had locked up within its 
kernel the elements which are most needed to maintain heat, 
and replace the energy and tissue which are constantly being 
worn away during life's processes. ;The savage in his hunger 
seemed to have instinctively turned to it as a food, and the wis- 
dom of his choice can readily be seen by a study of its composi- 
tion as given by Dr. H. W. Wiley, formerly of the United States 
Department of Agriculture. 

Water 10.60 

Protein 12.25 

Fat s 1.75 

Fiber 2.40 

Starch, etc 71.25 

Ash 1.75 



J?OOD INDUSTRIES 2)7 

Geographical Distribution. — The raising of wheat has so long 
been a practice with man that the geographical origin is unknown. 
Egyptians attribute its discovery to Isis and the Chinese claim 
to have received the seed as a direct gift from Heaven. It was 
at one time the custom for the Chinese Emperor to drive the 
plow in order to do homage to the dignity of agriculture. The 
belief that it originated in the Valley of the Euphrates and Tigris 
is more widely accepted than any other theory. Early it spread 
into Phoenicia and Egypt, finding a most suitable lodging place 
along the shore of the Mediterranean. The climate there was 
suited to its cultivation, dry and hot during the summer months. 
Italians as far back as the early Roman days obtained part of 
their wheat supply from the north of Africa, for that war-like 
nation was unable to produce enough wheat for its own con- 
sumption. Many of their warfares were for the purpose of 
capturing the harvest from their more successful wheat growing 
neighbors. 

' The migration of wheat from those early days was closely 
connected with the migration of the human race. Gradually 
spreading throughout Europe, it finally reached Germany, 
France and Great Britain, although this latter country has never 
been able to grow enough wheat to supply its population. Great 
Britain still obtains much of its wheat from countries where con- 
ditions are more favorable for the growth of this cereal. Extend- 
ing into Russia, wheat once more found a suitable soil and 
climate which in time produced so large a supply, that Russia 
became known as "The Granary of Europe." That title she 
continued to keep until the famine of 1891-92 swept the country 
with a terrible scourge and from which she has never fully recov- 
ered. \ The failure of the crops during those years was caused 
not only by bad weather, but by the continued use of crude agri- 
cultural methods which in time thoroughly impoverished the soil. 
Should she use more up-to-date methods in regard to fertilizing, 
she might again regain that title, but the yield per acre at present 
is very small. The peasantry still cling to old methods slightly 
in advance of the Middle Ages. In Russia, there are still 



3& FOOD INDUSTRIES 

immense undeveloped areas that would make ideal wheat fields 
and much is being looked for in the Siberian wheat-growing 
area. It is difficult to predict, however, what part the Russian 
Empire will play in the wheat market of the future. The possi- 
bilities are very great, but many changes must first be brought 
about in the political and social condition of the people, for 
Russia is still sadly lacking in the institutions that are necessary 
to bring about progress and prosperity. Even with these great 
drawbacks Russia is still one of the greatest wheat producing 
countries of the world, largely due to the Siberian wheat fields. 

When civilization moved westward, it was found that wheat 
could be grown in the New World for that cereal readily adapts 
itself to new environments. Starting along the Atlantic coast, 
it pushed farther and farther westward with the march of civili- 
zation, flourishing wheat fields shortly replacing the primeval 
forest. When the wheat line had reached Ohio it was thought 
by many European nations to have reached its limit on American 
soil. Warning was given to the Ohio farmer to care for the 
soil, for with the rapid growth of the United States it was feared 
that the population would soon outrun its wheat production. 
But the wheat line was not to stop; in the opening up of the 
northwest, this cereal was again to find favorable conditions for 
its growth. With fertile soil, intellectual farming, American 
enterprise and capital, the United States advanced to one of the 
leading wheat producing nations of the world. 

Still farther north the wheat line was to travel, for it has been 
found in recent years that thousands of acres of land in Canada, 
which were considered waste land, can be utilized for wheat 
growing. This area is nearly three times as great as that used 
for wheat in the United States and the yield per acre is larger. 
As yet only about 5 per cent, of the land is under cultivation. In 
Canada the United States has found a powerful rival. The 
virgin soil is capable of producing enormous crops of superb 
spring wheat, much needed to blend with softer varieties, and 
the men behind the plow in this new wheat-producing country 
both read and think. 



FOOD INDUSTRIES 39 

\ It would seem that with the development of the northwest 
area that wheat had at last reached its limit of cultivation on 
American soil, but agriculturalists prophesy that the line of 
march will next turn eastward, and that much land now lying 
idle in the eastern and southern sections will in time be utilized 
for the growing of wheat. With the development of drought 
resistant varieties, it is also hoped that more of the semi-arid 
land of the west can be used.; 

Of the South American countries, Argentine Republic has 
taken the first place as a producer and exporter of wheat. Here 
are found great natural advantages, extensive prairies very sim- 
ilar to those of Minnesota and the Dakotas, and a moderate 
climate which enables the farmer to work the land almost any 
time of the year. Cheap land, cheap labor and its nearness to 
the sea are also important factors. As in Russia, however, agri- 
cultural methods are still very crude. Land is not well cared 
for and the crops are not properly stored. This latter deficiency 
sometimes affects wheat to be used for milling. With improved 
conditions, Argentina promises to be an important wheat pro- 
ducer. At the present time more wheat is being raised than is 
necessary for home consumption, and large quantities are being 
shipped to Europe. 

While Russia, United States, Canada and Argentina have been 
the most important wheat-producing countries, this cereal can be 
cultivated in a variety of climates. Regions having cold winters 
produce most of the world's wheat, but marked exceptions are 
found in Egypt arid India. While Egyptian wheat is of little 
commercial importance to-day, in the age of the Pharaohs and 
during the Roman civilization, Egypt was the wheat center of 
the world. 

Cultivation. — Wheat has always been a cereal that has needed 
the care of mankind; wild varieties are practically unknown. 
Little is told us in history of how the farmer of antiquity tilled, 
sowed and harvested his crop and it was not until the days of 
the Roman Censor, Cato (234-149 B. C), that any written work 
can be found on the subject of agriculture. The tillers of the 
4 



40 FOOD INDUSTRIES 

soil have always been marked by their independence, and it was 
not until modern times that we found co-operation among this 
class of workers. The early farmer worked many times in a 
more or less isolated position, independent and non-progressive, 
teaching his son and grandson to follow in his footsteps. For 
information as to the time of sowing, he had only the deities and 
medicine-men to consult. For centuries the farmer was left to 
work out his own salvation, but with the advance of civilization 
very gradually there arose the botanist, the physicist and chemist, 
the agriculturist and the bacteriologist to assist him in his work. 
So important is the work of the scientist in modern times that a 
single government has been known to spend many millions of 
dollars in the solution of a problem of great importance. Shortly 
after the colonists had established their independence, the sug- 
gestion was made to establish a national board of agriculture, 
but it was not until the days of Lincoln that the National Depart- 
ment of Agriculture was established. The experimentation car- 
ried on by Liebig and other scientists of his time led the way to 
the foundation of experiment stations, and in time to agricul- 
tural colleges both in Europe and America. Farmers' institutes 
and societies followed which have now grown to be of national 
importance. 

Hand in hand with the progress of agricultural methods is 
found the progress in motor power. For centuries, undoubtedly 
only the muscular energy of man was used, and hand labor is 
still employed to a large extent in India, China, Japan, Egypt, 
Mexico and among many of the Eastern and South American 
nations. Animal power was the first that relieved man from the 
drudgeries of agricultural life, the oxen and the horse being 
almost universally employed. This power is still largely used, 
although as early as 1832 steam power was introduced into Eng- 
land, and is now used to a great extent in the Western United 
States and in parts of Germany and Hungary. Much experi- 
menting is being done along the lines of electricity. As in motor 
power, so in implements can the progress of the world be seen 
by a comparison of the early plow as seen on Egyptian monu- 



FOOD INDUSTRIES 



41 



merits with the modern combined harvester of the great north- 
west. 

Structure of the Wheat Grain. — (Figs. 8 and 9.) I. Husk. — 
The husk is the outer layer and serves as a covering, thus protect- 
ing the grain from the attack of its enemies in much the same way 
as the shell does the nut. It is composed largely of cellulose, a 
woody fibrous material not available as human food. 

II. Bran coats lie directly under the outer covering and are 




S^sf/V 



^fwr? olt/^zt ^^r 



G<?/*c/*r 



Fig. 8. — I/sugitudinal Section Through a Grain of Wheat. 

composed of several distinct layers mostly cellulose impregnated 
with mineral matter. Here too are found cells full of pigment 
which give to the bran its characteristic color. Directly under- 
neath the bran coats is found a single layer of large cells full of 
granular material of a protein nature. This coating completely 
encloses the endosperm and germ and is usually spoken of as the 
layer of aleurone cells or the cerealine layer. 

III. The endosperm is the largest and most important part of 



42 



FOOD INDUSTRIES 



the kernel; it is the food part of the grain, the portion utilized 
in the making of ordinary flour. It contains cellulose in the cell 
walls, a small amount of mineral matter, sugar and practically 
all of the starch and protein available as food. Nature designed 
it to serve as food for the young plant during the early stages 
of growth. 







Fig. q.— Section Through Part of a Grain of Wheat. 
a — Cellular Structure. £— Starch Granules, c — Protein. 



IV. The germ is the part from which the plant is to be repro- 
duced. It is more complex in its composition, containing cellu- 
lose and soluble carbohydrates, a large proportion of nitrogenous 
matter and is rich in oils and mineral matter. 

Value of Wheat. — Its wide adaptation to different climates and 
soils, the ease of cultivation, a quick and abundant harvest, great 
number of varieties and the intrinsic food value of the kernel 
would be sufficient to make wheat the leading food grain. There 
is still another reason, however, which gives it the rank of 
king among cereals. This lies in the fact that it . can be so 



FOOD INDUSTRIES 43 

readily utilized in the making of bread. This quality wheat 
shares only with rye and both owe their bread producing power 
to the nitrogenous constituents of the endosperm. 

Osborne and Voorhies in their investigation of the protein 
content of wheat discovered five distinct proteins, the most 
important of which were gliadin and glutenin, both occurring in 
the endosperm in about the same amount, 4.25 per cent, of the 
entire grain. In the presence of water these proteins unite to 
form gluten. To the peculiar properties of this gluten, wheat 
bread owes its lightness and digestibility, thus giving it first place 
among the civilized nations of the world. The other cereals con- 
tain similar proteins, but not in the right proportion to form 
gluten. With rye flour, gluten can be formed, but it does not 
make as light or as acceptable a loaf. 

Varieties. — Migrating as it has for many centuries, meeting 
different conditions of climate, soil and methods of cultivation, 
wheat is now grown in a vast number of varieties. The United 
States Department of Agriculture after long experimentation 
reduced the number to 245 leading varieties. For the sake of 
convenience wheat can be divided into two large classes, winter 
wheat and spring wheat. 

Winter Wheat.— Fox the varieties of winter wheat, seeds are 
planted in the fall. Enduring the cold and dampness of the 
winter, a maximum of starch and a minimum of protein are 
developed in the endosperm. Flour made from this wheat is 
soft and does not give enough gluten to make as desirable a 
loaf of bread as spring varieties, yet it was the flour used among 
the so-called civilized nations of Europe until the time of Eiebig. 
He was the first to suggest that the right kind of flour was not 
being used for bread-making. Either the process of milling 
must be changed or a new wheat must be grown. His experi- 
mentation was along the lines of agriculture, to grow a variety 
higher in gluten- forming proteins and lower in starch content. 

Spring Wheat. — Amid much ridicule and after many failures, 
Liebig finally convinced a*griculturalists that wheat for bread- 
making should be grown quickly. The temperature was most 



44 FOOD INDUSTRIES 

important ; dry, hot weather was necessary. Seed if planted in 
the spring would ripen in the early summer or fall and be ready 
for harvesting in August or September. This opened a new era 
in the cultivation of wheat. Soon a hard spring wheat was 
being grown that in time was utilized largely for the making of 
bread. An extended study of its production brought about many 
reforms along agricultural lines which were also felt by the 
growers of winter wheat. These new ideas have enabled farmers 
to grow many varieties of winter wheat higher in their protein 
constituents than the first spring wheat grown. With the devel- 
opment of hard spring varieties, new milling processes were 
found necessary, the development of which was to place the 
miller among the world's manufacturers. 

OLD MILLING PROCESSES. 

The history of wheat would be far from complete without a 
study of milling processes, for the story of wheat must ever be 
intimately connected with the history of the production of flour. 
Here again we find wonderful progress from the rude processes 
of ancient civilizations to the modern roller mills, where can be 
seen the greatest mechanical perfection and whose capacity is so 
great, that they can produce in a single day enough flour to feed 
a small city for an entire year. 

It has been suggested that wheat was first eaten raw, for when 
driven by the pangs of hunger primitive man plucked the wheat 
grain from the stalk, using his teeth as mill-stones, and that it 
was this grinding motion which first gave him the idea of invent- 
ing some rude instrument which would break up the hard berry 
for him. Whether this idea be true or not, we find that various 
forms of apparatus were early invented to make the grinding 
process easier and more effective. All primitive nations reduced 
grain to a meal by means of a hand-stone. 

Hand-stones. — The form of these stones was varied, but they 
all consisted of two stones, one of which held the grain while the 
other was used for pounding. Fig. 10. The first real grinding 
came into use when the lower stone was given a concave surface 



FOOD INDUSTRIES 45 

and the grain being placed within the hollow was rubbed back 
and forth by means of a stone-crusher. These primitive mills 
were always operated by women and were the only mills used 
for some four thousand years. They must have been used by 
the aboriginals of all countries, for large numbers of them have 
been found showing their use among the prehistoric Swiss lake 
dwellers, the Babylonians, the natives of Nineveh, Assyria and 
Egypt and again in many parts of the New World. So far as 
their structure, detail and finish are concerned, tablets indicate 
that saddle-stones made this side of the Atlantic were superior 
to those of Europe and Africa. Milling was not a separate indus- 
try, but part of the work of each household in which the meal 




Fig. 10. — Hand-stone. 

was first made then baked into cakes or bread. In some parts 
of the world this operation is still carried on. In sections of the 
northern part of Africa women are the millers, doing their work 
in saddle-stones in much the same way as it was done . in the 
earliest historic times. 

The Mortar and Pestle. — In time the stone-crusher became 
elongated into the pestle, and the saddle-stone was fashioned into 
the mortar (Fig. n). This marked the step from barbarism into 
civilization. In the mortar period the Greeks substituted men 
as flour-makers. These men were called pounders and in the 
decline of Grecian supremacy, a band of them were led captives 
into Rome. As prisoners of war, these craftsmen were set to 



46 FOOD INDUSTRIES 

work at their occupation, grinding and baking. From this fol- 
lowed the custom of using slaves as the millers during the days 
of the Roman Empire. 

Quern. — To the Romans, the ancient world was indebted for 
inventing the first milling machine in which the parts were 
mechanically combined. It was a simple grinding machine giving 
a circular motion and was known as the quern. It consisted of 
two stones, the upper one conforming to the shape of the lower 
upon which it revolved. This upper stone was hollowed out in 




Fig. 11. — The Mortar and Pestle. 

the center, making a hole sufficiently large to receive the grain 
to be ground and had on the side a handle to facilitate the turn- 
ing of the stone. This was the mill in use at the dawn of the 
Christian Era and it still can be found in China, Japan, among 
the Arabs and in some isolated sections of Europe. It was the 
original British flour mill arid was destined in that country to be 
the cause of a long political strife. In the early days of the use 
of the quern, women did the grinding, but gradually this work 
was given to slaves and criminals. The first marked improve- 



FOOD INDUSTRIES 47 

ment was the grooving of the grinding faces of the stones and 
in time the enlargement of the mill. 

As the quern increased in size another motor power was found 
necessary. This for a long period in many countries was sup- 
plied by cattle, although in parts of northern and western Europe 
the water mill early came into use. With the enlargement of 
the mill and the introduction of different motor power, milling 
passed from the household to the hands of the professional 
miller, who at first did the village grinding, then passed to a 
larger district. In some countries wind was used instead of 
water and we find crude wind-mills appearing as early as 600 
A. D. The earliest mills of the United States were operated by 
horse-power, wind and water being later introduced. 

Grist Mills. — While the motor power was being changed, devel- 
opments appeared in the mill-stones and the grist mill came into 
existence. At the end of the eighteenth century this mill, driven 
by either wind or water, was doing a thriving business and it is 
only a comparatively short time, since it had to give away to the 
modern roller mill. The structure at first was of few parts and 
the operation was simple. The entire wheat went into the flour; 
there was no bolting and no separation into grades. The grain 
was at first crudely cleaned by screening, blasts of air being 
passed over the wheat to blow away chaff and lighter particles. 
The wheat was then passed to the mill-stones to be ground. Two 
large stones known as burr-stones were used, the lower one of 
which revolved. They were very heavy, sometimes weighing 
1,500 pounds, and as a rule were imported from France. The 
stones were made up of pieces bound together with bands of 
iron. The inner surface was cut much like a grater and, as it 
wore smooth, the miller would again cut its surface with a steel 
pointed hammer called a mill-pick (Fig. 12). j When the two 
stones touched in revolving, it was spoken of as "low milling." 
The grain was fed from above and the grinding motion con- 
tinued until the kernel was ground to a powder. The outer 
husks were torn into shreds and the germ, being plastic, rolled 
over and over until it assumed a cylindrical form. The main 



4 8 



FOOD INDUSTRIES 



object of low milling was to make the largest possible amount 
of flour from the grain at the first grinding. The only separation 
made was that of the fibrous part which being lighter could be 
removed by a process of winnowing. As some of the bran was 




Fig. 12 — Roughening Burr-stones. 
(Courtesy of the Washburn-Crosby Co., Manufacturers of Gold Medal Flour.) 

pulverized it was impossible to separate it from the flour. This 
gave the flour a dark color and impaired its keeping qualities. 
The germ also being rich in fat in time became rancid. 

During the nineteenth century marked improvements took place 



FOOD INDUSTRIES 49 

in milling owing to the invention of many mechanical devices. 
Screens and bolters came into use which led to a practice of sift- 
ing and regrinding. The elevator, the conveyor, the drill and 
the hopper-bag were invented and finally the middling purifier. 

With the invention of the middling purifier, "high milling" 
came into use. Here the stones were placed farther apart and 
the wheat was granulated rather than ground, sifted and re- 
ground. This gradual reduction being found advantageous, more 
stages were introduced until a flour vastly superior in quality 
was being placed upon the market. 

When hard spring wheat, however, appeared other improve- 
ments were necessary. When our people visited Hungary, they 
were surprised to find what progress had been made along 
mechanical lines. There the grain was being crushed by means 
of rollers made of porcelain. Americans were very quick to see 
the advantage of this process and a roller-mill outfit was brought 
from Hungary to Minneapolis. Many changes in machinery 
were necessary to meet new conditions, but from 1881 the roller- 
mill rapidly increased, and before the dawn of the twentieth cen- 
tury the long honored grist mill had practically disappeared. The 
substitution of rolls for mill-stones was the most radical advance 
ever made in the history of milling. It made possible the opera- 
tion of large flour mills which rank among our great commercial 
industries. 

Disadvantages of Old Processes. — I. They were very slow. In 
the grist mill the stones were very heavy and could not be driven 
rapidly. 

II. The flour could not be ground as fine. If the stones were 
placed too close together, there was danger of the stone itself 
wearing away and becoming mixed with the flour. 

III. Friction caused heat which would affect enzyme action. 
Starch would be changed to a more soluble form and thus make 
the flour more liable to be attacked by molds and bacteria. 

IV. The keeping quality was very poor. Farmers in olden 
times were in the habit of carrying grain to the mill in sacks and 
carrying home flour. It was said that the farmer was poor or 



5° 



FOOD INDUSTRIES 



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FOOD INDUSTRIES 5 1 

that he could not conveniently carry more, but these were not 
the true reasons. He had learned by bitter experience that the 
flour would not keep. It was long before the cause for this was 
known. Old-fashioned flour contained the germ within which is 
most of the oil of the wheat kernel. Oil becoming rancid soon 
spoiled and ruined the flour. In modern milling processes the 
germ is removed. 



CHAPTER IV. 



MODERN MILLING AND MILL PRODUCTS. 

In visiting a modern mill, a curious device invented for the 
safety of the mill at once strikes the eye of the visitor. This is 
called a dust-collector. The milling of wheat always produces a 
large amount of flour dust which in case of ignition is capable 
of causing a terrific explosion. A disaster of this kind in the 
Minneapolis mills during 1877-78 led to the development of a 
large rotating diaphragm, which by suction collects flour dust 
from the various machines used throughout the mill, thus keeping 
the atmosphere comparatively free from dangerous particles. 

To the novice there appears to be innumerable processes in- 
volved in the present day milling of wheat. From the time the 
grain is received, however, until it is packed for shipment as 
flour, the miller has in mind several fundamental objects; the 
thorough cleansing of the wheat, tempering, separation out of 
the middlings and the reduction of the middlings to flour. 

After the grain is received and weighed, it is carried at once 
by means of elevators to the top of the mill where it passes 
through a preliminary process of cleaning. 

I. Cleansing of the Wheat. — Receiving Separators. — These 
separators consist of several large sieves for separating out 
from wheat such matter as corn, sticks, stones, lint and nails. 
The sieves are kept constantly in motion, are slightly inclined 
and have holes sufficiently large to allow the wheat kernel to 
pass through. Foreign matter being retained passes down the 
incline and is caught in a receptacle. 

Storage Bins. — From the receiving separators, wheat passes 
by conveyors to the storage bins for a reserve supply in advance 
of mill requirements. 

Mill Separators.— When required for milling, wheat is drawn 
to the mill separators. Here are a series of sieves constantly 
shaking for removing dust, dirt, foreign seeds such as oats and 
imperfect kernels of wheat. Perforations are smaller than those 



FOOD INDUSTRIES 53 

of the receiving separators and hold back the wheat while foreign 
and imperfect grains pass through. 

Scourer. — During the sifting processes the dust and dirt have 
not been fully removed. In this machine wheat grains are 
thrown against perforated iron screens. This loosens the dirt 
while a strong current of air passing through draws it out. Some 
scouring machines have brushes attached for brushing and pol- 
ishing the grain. 

Cockle Cylinder. — In the wheat fields there is a common weed 
known as the cockle. It has a small, round, black seed which 
frequently becomes mixed with wheat and must be separated out 
or the quality of the flour will be impaired. As they follow the 
wheat kernel in the receiving and mill separators, a special 
device has been invented for their removal. This is called the 
cockle cylinder. 

Washing Machine. — The washing process is usually not con- 
sidered necessary in mills, where scourers or the dry process of 
cleaning as it is called has been used, unless in case of special 
contamination. Some millers, however, prefer to wash all wheat, 
afterwards carrying it through a drying process. 

II. Tempering. — This operation is carried on to make easier 
the separation of the outer part of the wheat kernel and is 
especially necessary with spring wheat. There are many methods 
of tempering, but all consist in a softening of the grain by means 
of heat and moisture. This may be accomplished by steam or 
water or by the application of both. The grain comes through 
this process having a warm, moist feeling and ready for the 
grinding process. 

III. Separation of the Middlings.— Roller Mill— The mill (Fig. 
13) consists of two or three steel rolls about 2 feet long and 
having small teeth on the outer surface for the purpose of cutting 
the berry. They rotate at different speed. The grain passes 
from the rolls, ruptured and flattened and feeling like damp saw- 
dust. The pieces are comparatively large for the reduction by 
the roller-mill process is gradual. 

Scalper. — As the grain passes from the first roller or "break" 



54 



FOOD INDUSTRIES 



as it is sometimes called, it consists of bran coats and the interior 
of the wheat which is known as the "middlings." A sifting 
process is next necessary to separate out as much of the bran as 
has been loosened. The sieve consists of a series of screens 
usually covered with wire or bolting cloth and is known as the 
scalper. 




Fig. 13.— Roller Mills. 
(Courtesy of the Washburn-Crosby Co., Manufacturers of Gold Medal Flour.) 



Second Roller or Break. — The first separation was very crude, 
for the bran coats still carry much of the interior with them. 
To separate out this material, the bran is again passed through 
a roller-mill, the principle of which is the same as the first 



FOOD INDUSTRIES 



55 



"break," but the rolls are set closer together. This tears the 
bran into smaller pieces and frees more of the interior. 

Second Scalper. — This finer product is again sifted and more 
middlings are separated. The bran is now ready for a third 
grinding. The operations of rolling and sifting are carried on 
again and again, four, five, six or more times or until all the 
middlings have been obtained. The bran can be used as cattle 
food. 




Fig. 14. — Middlings Purifier for Taking Impurities from the Crushed Grain. 
(Courtesy of the Washburn-Crosby Co., Manufacturers of Gold Medal Flour.) 

IV. Reduction of the Middlings. — The middlings obtained from 
the various rollers and sifters are mixed and constitute the part 
that is to be made into flour. There are three important machines 
met with in this operation — the purifier, the smooth roller or 
pulverizer and the bolter. 
5 



56 



FOOD INDUSTRIES 



Purifier. — The middling purifier (Fig. 14) is very complicated 
in its mechanical structure, but simple in principle. It consists 
of different mesh sieves about eight in number. The middlings 
are fed into the machine from above, flow down in a thin sheet 
while a current of air fed from below passes outward, carrying 
off small particles of remaining bran. Wheat being heavier 
passes down through the sieves and is caught in a receptacle 
from which it is conveyed "to the smooth roller. 




Fig. 15. — The Modern Sieve or Bolter. (Courtesy of the Hecker-Jones-Jewell Milling Co.) 

Smooth Roller. — These rolls are made of steel and, as the 
name indicates, are smooth. They are really pulverizers. The 
purified middlings passing under the smooth roller are ground 
fine; this is the first reduction to the powder form, although not 
all is reduced to the same degree of fineness. This difference 
necessitates further separation and treatment. 

Bolter. — The bolter (Fig. 15) is a large machine containing 



FOOD INDUSTRIES 57 

some 360 sieves made of silk bolting cloth with varying mesh. 
The machine moves with a side motion and makes from eight to 
twelve separations of the material. The fine flour is thus sepa- 
rated from the middlings and any remaining bran. Separation 
gives bran, middlings and fines. Fines represent flour. All 
coarser parts again go through the purifier and smooth roller 
repeatedly, finally being separated by the bolter. When the 




Fig. 16.— Bolting Reel for Separating the Flour from the Bran. 
(Courtesy of the Washburn-Crosby Co., Manufacturers of Gold Medal Flour.) 

separation is complete the flour is ready to be automatically 
packed in bags or barrels. The germ is separated out by the 
purifier during the early stages of the refining process as it gives 
a yellow appearance to the flour and impairs its keeping qualities. 
Advantages of the New Process. — I. Increased capacity. The 
roller-mill has greater strength ; there is greater centrifugal force, 
the mill can be driven faster. 



58 FOOD INDUSTRIES 

II. Much less power is required to run the machinery; elec- 
tricity is now used. 

III. Present day process is much cleaner. All foreign matter 
is removed in different siftings, brushing and washing. The 
purifier showed marked progress in cleansing. From the time 
that the grain enters the mill until it is ready for shipment as 
flour, the human hand does not touch the wheat. It is carried 
from place to place, from process to process entirely by eleva- 
tors, conveyors and other mechanical devices. 

IV. The separation is much more perfect, only the part which 
is desired (the endosperm) is found in flour. 

V. It is much more economical as there is less waste. In the 
old process much that was valuable was carried off in the bran; 
the working over this material again and again saves about 8 per 
cent, on each bushel. The price of flour is cheaper now than in 
former years. 

VI. Rollers do not touch, so small particles of steel are not 
often found in flour. Should there be any, they can be removed 
by passing flour through a magnetic zone. This process was 
thought necessary in the early days of the roller-mill, but it is 
now seldom used. 

VII. Modern flour keeps better, the germ has been removed 
and there is less heat by friction, so fewer undesirable changes 
take place. 

Testing of Flour. — The material is tested at different stages of 
the process and again on the finished product before the flour is 
shipped. Except in comparatively few mills the tests are very 
simple ; usually the quality is told by texture, color and by making 
it into bread. In the large modern mills may occasionally be 
found laboratories where, by chemical testing of the various 
kinds of wheat and flour, scientists are co-operating with the 
millers in the production of finer quality flour. The chemist's 
advice is particularly desirable in the blending and mixing of 
wheat to be used for flour making and in the manufacture of 
cereal products. 



FOOD INDUSTRIES 59 

Wheat Blends. — One of the greatest problems that the miller 
has to meet is the production of a uniform quality of flour. A 
poor grading of wheat, or even changes which occur in the 
quality of the grain from season to season, necessitate a careful 
selection of wheats for blends on the mill. Wheats must be so 
blended that the "best qualities of each have the greatest chance 
of being effective in the resulting flour." A careful analysis of 
various wheats as to their starch and protein content, and the 
determination of the quality of the gluten in flour, greatly assist 
in the blending of winter and spring wheats of different strength. 
Successful blending usually insures that which the miller most 
desires, the uniform quality of his products. 

Adulteration. — Many substances have been used to adulterate 
and cheapen flour. The most common custom has been the 
grinding of foreign matter with wheat or an admixture of starch 
from rye, corn, rice or potatoes. Occasionally, mineral matter 
such as alum, borax, carbonate of magnesia and various clays 
have been discovered. The United States Department of Agri- 
culture, however, has found that very little adulteration of any 
kind has been practiced in this country. 

Bleaching of Flour. — In former years flour was artificially 
bleached by using electrical or chemical means to make an inferior 
article resemble a superior one. While this custom still prevails 
in some countries, the bleaching of flour has been forbidden in 
the United States under the Food and Drug Act for interstate 
commerce. 

MILL PRODUCTS. 

The leading mills usually put out as many grades of flour 
as the market demands, blending spring and winter wheat of 
different grades. Generally speaking, flour is divided into four 
grades: (i) high grade patent; (2) bakers; (3) second grade 
patent, and (4) red dog. Red dog is so inferior in nutritive 
value that it cannot be sold as food; it is used largely for the 
making of paste. 

Flour can also be divided into hard and soft varieties. 



60 FOOD INDUSTRIES 

Hard Wheat Flour. — Hard wheat flour is made from spring 
wheat and represents the type now used almost universally for 
bread-making. It is rich in tissue building elements and gives 
the largest yield of gluten so necessary in the making of a light, 
porous loaf of bread. 

Soft Wheat Flour. — This flour is made from winter wheat and 
has more starch and less gluten than hard wheat flour. It can 
be utilized for bread-making, but it is less nutritious and has a 
poorer flavor. It is often spoken of as pastry flour and is used 
largely for the making of cakes, pastry, crackers and the so-called 
"quick breads" as biscuit and muffins. Soft wheat flour, having 
less gluten, is particularly desirable for these products. 

Spring and winter wheat flours can be detected by simple 
experiments. Hard or spring wheat flour, on account of its 
gluten content, absorbs more water, has a gritty feeling and is 
deeper in color, having a yellowish rather than a white appear- 
ance. Soft wheat flour, having a large percentage of starch, 
cannot take up as much water ; it forms a more pasty dough. 
It is white and has a soft velvety feeling when pressed between 
the fingers. 

Prepared Flour. — This product is a so-called "self-raising" 
flour and has little commercial value. It consists of an ordinary 
flour mixed with other flour as corn and rice, salt and such 
ingredients as are found in baking powders, as ■ bicarbonate of 
soda and acid potassium phosphate. The addition of water 
causes the bicarbonate and acid salt to unite chemically and 
carbon dioxide is given off. This gas in expanding gives a light 
spongy dough. Prepared flour is very convenient but more 
expensive than ordinary flour and baking powder. 

Graham Flour. — In the history of milling there is still another 
side which has received much attention — how much of the wheat 
berry should be utilized as food? 

In primitive milling the entire kernel except the husk appeared 
in the flour, but the refining processes of modern times had 
reduced this to the use of the endosperm only. During the 
nineteenth century there was much discussion in regard to the 



FOOD INDUSTRIES 6 1 

starchy nature of the flour; it contained only 8 per cent, protein 
and 3 per cent, mineral matter. This was the kind of flour that 
started experimentation by Liebig, which resulted in the produc- 
tion of a harder variety of wheat. Other experimenters were 
also at work on the problem, among them an Englishman by the 
name of Graham. Graham was a great temperance worker. In 
the hope of curing alcoholism, he recommended a change in diet, 
especially advocating an abstinence from meat. To supply this 
deficiency in nitrogenous matter, he suggested the use of bread 
having a higher protein percentage. To obtain such a flour 
Graham suggested the use of unbolted wheat, that is, the use of 
the entire wheat berry. This was practically a return to the 
earlier method of milling and produced a bread darker in color 
and having a coarser texture. Much agitation of the question 
followed, but people had learned to prefer white bread, and 
Graham bread, as it was called, never became popular in the diet. 
On investigation by scientists, Graham bread was found to 
contain more protein and mineral matter than white bread, but 
it passed through the intestines more rapidly. At that time, this 
was thought to be caused by the mechanical action of the bran 
on the lining of the intestines ; the bread was carried away before 
the system had extracted all the nutritive matter that it was sup- 
posed to yield. Evidently Graham had not solved the question 
of the starchy flour of his day. Liebig was far more fortunate, 
and in the cultivation of hard wheat a higher percentage of pro- 
tein has been obtained than was found in the original Graham 
flour. 

Entire Wheat Flour. — Just before the introduction of the Hun- 
garian method which so improved the milling process another 
attempt was made along the lines Graham had worked. This 
resulted in the introduction of what is known as whole or entire 
wheat flour. This flour is prepared by a process very similar to 
that used in the milling of Graham flour, except that after the 
cleaning processes the outer bran coats are removed before the 
berry is ground into flour. Entire wheat flour, therefore, contains 
not only the endosperm but the layer known as the aleurone 



62 



FOOD INDUSTRIES 




a , 3°7-7 grams of bread from 227 grams of Graham flour ; b, 302.5 grams of bread from 
227 grams of entire wheat flour; c, 301.5 grams of bread from 227 grams of standard 
patent flour. 




a, Feces from Graham bread ; b, feces from entire wheat bread ; c, feces from standard 

patent bread. 



Fig. 17. — Bread Made from Entire-wheat, Patent, and Graham Flours, and Character of 
Feces from Same. (Courtesy of the U. S. Dept. of Agriculture.) 



FOOD INDUSTRIES ' 63 

cells. This is not present in patent flour, being removed as shorts 
or middlings. 

Upon investigation it has been found that entire wheat bread 
also acts as a laxative, although not to the same extent as Graham 
bread. This is now believed to be due to the peculiar character 
of the protein and mineral matter of the aleurone layer. Possibly 
this is the main cause in Graham bread, although it was for a 
long period believed to be entirely due to the action of the bran 
coats. Much discussion followed as to the relative value of 
entire wheat and patent flour. As regards composition, the 
difference lies entirely in the protein and mineral matter of the 
aleurone layer. Composition, nevertheless, does not tell the 
whole story, for the important question is — how much of the 
wheat kernel is available as food? White flour contains the 
gluten forming proteins which are the most important and be- 
lieved by many scientists to be all the protein that is available 
as food (Fig. 17). Undoubtedly the claims made by manufac- 
turers as to the value of the whole wheat flour have been greatly 
over-estimated, although its use occasionally gives a pleasant 
change in the diet. 

Gluten Flour. — Gluten flour is a substitute for patent flour, 
much used by people having diabetes or such diseases that the 
use of starch is undesirable in the diet. It is prepared from an 
ordinary good grade flour. Flour is mixed with water and 
allowed to stand. In time the starch washes out and if allowed 
to settle, a separation can be made. Repeated washings are given 
until the starch is not over 50 per cent. The product is then 
dried and reduced to a powder. This process requires time and 
is troublesome, and the manufacturer should be paid for his 
labor. The sale price for such flour should be approximately 
22 cents per pound. A cheaper product is sometimes found on 
the market selling for 7 cents per pound. Manufacturers could 
not afford to put flour through this process and sell it at so low a 
figure; cheap gluten flour is simply a low grade flour containing 
bran. 

Cereal Department. — Many of the large mills have a cereal 



64 FOOD INDUSTRIES 

department where the so-called breakfast foods are manufac- 
tured by processes quite similar to those of the milling of flour. 
For further information see Chapter VI, Breakfast Foods. 

Seminola. — The preparation from wheat of a coarse meal 
known as "Seminola" is now largely carried by the miller. Semi- 
nola is used in the preparation of macaroni. See page 105. 

RYE. 

Rye is a species of grain resembling wheat. During the 
Middle Ages it furnished much of the bread material for the 
great body of people in Europe, and is still extensively used in 
Russia and Germany by the peasantry, although it is gradually 
being superseded by wheat. Its cultivation is evidently not 
nearly as old as the other cereals, for there is no mention of it 
in ancient languages. It was known, however, to the Romans 
in Pliny's time. 

Rye is a very hardy plant and will grow in a soil too poor for 
the majority of other food grains and too cold for the produc- 
tion of wheat. It thrives best and gives the largest yield under 
conditions favorable to wheat. The varieties grown are not 
nearly as great as the other cereals ; the principal varieties are 
known as winter and spring rye. 

Composition. — The starch content is much like that of wheat, 
a difference being detected only in the microscopic appearance 
of the granules. The nitrogenous constituents also resemble 
wheat as far as gliadin is concerned. There is no protein, exactly 
corresponding to glutenin ; therefore, the gluten formed is not 
altogether similar to that prepared from wheat flour. It more 
closely resembles wheat gluten, however, than any other cereal 
and can be successfully used with or without a leavening agent 
for the making of bread. 

Uses. — Rye ranks second as a world's bread material. Rye 
bread is highly nutritious, but is less pleasing to the eye than 
wheat bread. It is dark in color, moist and compact in texture 
and has a peculiar sour taste. An extreme example is the black 
bread or pumpernickle of North Germany. A partial rye bread 



FOOD INDUSTRIES 65 

is often made by mixing the flour with wheat flour. This gives a 
larger yield of gluten and makes a larger and more palatable 
loaf of bread. Rye flour is used largely in the United States, 
but chiefly by the foreign born population. 

Rye is excellent for the production of malt used in the dis- 
tillation of spirits, and is much used in Europe for the making 
of gin and in this country for the manufacture of whiskey. 

The bran can be used as a cattle food and the straw for hats 
and in the manufacture of paper. 

Adulteration. — The adulteration of rye flour has been very 
frequent, flour of other cereals being added. Such admixture 
may be detected with the use of the microscope. The rye granule 
as a rule is larger than wheat and frequently has characteristic 
markings as a cross, slit or star. 



CHAPTER V. 



CEREALS. 



Biological Origin. — The botanist places cereals as belonging to 
the family of grasses, the long cultivation of which produces 
seeds which can be utilized as food. The word cereal can be 
traced to Ceres, the name of the Pagan goddess who was sup- 
posed to preside over the grains and harvests. 

Kinds. — The most important are wheat, corn, rice, oats, rye 
and barley. 

Geographical Distribution. — Cereals are extensively cultivated 
in all parts of the world except the Arctic region, and but few 
countries can be found which do not raise grain in some form 
as a staple food. The reason for the extensive utilization of 
these cereal foods can readily be seen. 

I. Being easily grown, they are comparatively cheap. 

II. There is little refuse as compared with such food products 
as meat, fish and shell-fish. 

III. They contain a fair proportion of nutritive value. 

IV. The keeping quality is excellent if the cereals are properly 
protected from dust and insects. On account of their dryness, 
they are not readily attacked by micro-organisms. 

V. They can be easily prepared for the table, are palatable and 
when properly cooked are not difficult of digestion. 

Use in Our Country. — The American people eat a great quan- 
tity of cereals. This is a natural outcome of early conditions in 
this country. When Columbus landed on the Western Continent, 
he found the native tribes had a cereal under extensive cultiva- 
tion. This the early settlers called corn, the European name for 
the leading cereal food of the country. So exclusively was this 
grain grown in the New World that in time the word lost its 
original meaning and came to be applied only to Indian corn or 
maize. 

Columbus is supposed to have carried grains of corn to Europe 
on his first return voyage, but its cultivation there spread very 
slowly. Although introduced into Spain at the end of the fifteenth 



FOOD INDUSTRIES 



6 7 



century, it did not reach France until a hundred years later. 
It was finally carried into Asia and Africa by the Portuguese. 
In the Western World it advanced with the progress of the white 
race. 



Average Composition of Grains in Different Forms 



Water Protein Fat Starch Fiber Ash 



Wheal : 

Grains 

Meal 

Flour 

Oats : 

Grains 

Meal 

Rye : 

Grains 

Meal 

Flour 

Corn : 
Grains 

Meal { ° ld P rocess 
\ New process 

Rice : 

Grains 

Polished 

Flaked 



12.0 
12. 1 
13.0 



10.0 
7.2 



II. o 
II. 2 



12.5 
II.4 
12.5 



I2.0 
12.4 
II.7 



II. O 
12.9 

9-5 



10.9 
10.2 



10.2 
6.7 



9-7 
8.5 
6.8 



7.2 
6.9 
7-9 



1-7 
i-9 

0.8 



4-5 
7-3 



2-3 

0.9 



5-4 
4.6 

i-3 



2.0 

0.4 
0.5 



71.2 
70.3 
75-3 



59-i 
65-9 



72.3 
80.0 



68.9 
72.8 
78.0 



76.8 
79-4 
79-5 



1.6 
0.7 



12.0 
3-5 



2.1 
0.8 



2.0 

1.4 
0.8 



1.0 
0.4 



1 -9 

1.2 
0.7 



3-5 
i-9 



2.1 
0.4 



i-5 
i-3 
0.6 



1.0 

0.5 
0.4 



INDIAN CORN OR MAIZE. 

Origin. — Indian corn or maize is indigenous to the tropical 
countries of America. The prevalent opinion is that it was a 
native of Central America and Mexico, and that it passed through 
the same stages of cultivation and dissemination as other cereal 
foods. It resembles the sugar cane of the tropics rather than 
other cereals and has the most beautiful and luxuriant growth of 
all the grain grasses. 

From Central America it is supposed to have spread into 
South America traces of it having been found in the ancient 
tombs of Peru, to the West Indies and finally into North 



68 FOOD INDUSTRIES 

America. It has been found in the prehistoric mounds of Ohio 
and in the cliff dwellings of the southwest, but never among the 
remains of Egyptian monuments, thus strengthening the belief 
that it is solely of western origin. 

Early Cultivation. — Evidently it had been cultivated long and 
extensively before the discovery of America, for by the time 
European travelers penetrated into the New World, maize was 
being grown by most of the North American Indians. When 
Cartier ascended the St. Lawrence, he found fields of it where 
Montreal now stands. The early chronicles of Virginia and other 
colonies contain many descriptions of its cultivation ; the white 
man first receiving this food from the Indian, then learning the 
secrets of its successful growth from his red brother. 

The climatic conditions seemed to have been particularly 
adapted for its cultivation — an abundant rainfall and a high tem- 
perature during the growing season. We read, too, in history 
of another possible reason for the successful growth of this 
cereal. All along the Atlantic coast the Indians made a practice 
of fishing. The menhaden, which is inedible, was placed at once 
on, the corn hills. After using the edible varieties of fish, it was 
also their custom to put the bones into the fields for fertilizing 
purposes. Modern scientists have discovered that these bones 
contain phosphates, the material best adapted as a fertilizer for 
corn. 

When the early settlers first received this food from the 
Indian, its excellence seemed to have quickly impressed itself 
upon them, for the history of the American Colonies was after- 
wards closely connected with the cultivation of this cereal. 

Varieties. — Popcorn, flint, dent and sweet corn represent the 
chief bulk, although there are some seven hundred varieties of 
corn grown in the United States. Most varieties have white or 
yellow kernels, but various other colors are represented, such as 
black, blue and red. 

Early Methods of Preparation. — Hulled corn was used early by 
the colonists and in time became one of our typical American 
foods, especially among the natives of New York and the New 



FOOD INDUSTRIES 69 

England States. Corn was taken in its dry state and immersed 
for several hours in a solution of wood-ash called lye. In time 
the outer coat became soft and could be removed by gently 
stirring without impairing the inner part. After careful wash- 
ing to remove the alkali it was ready for a long, slow process of 
cooking. The method of cooking used was an old Indian custom 
and strongly resembled our fireless cooker of to-day. Large 
stones were thoroughly heated by means of a fire and when 
sufficiently hot were piled around the utensil holding the corn. 
Along the coast seaweeds were used to cover it. The corn was 
kept in this heat until it was ready to be eaten. 

Old Milling Method. — The early colonial records tell us that 
the Indians pounded corn after parching it before an open fire. 
The handstones or "corn" stones were of the mortar and pestle 
type, closely resembling those used by primitive people the world 
over. Many of these ancient stones have been found near the 
Indian settlements in Texas as well as other parts of the United 
States. After crushing the corn to a coarse meal, sometimes 
nuts and berries or bits of meat and fish were added. The 
colonists took very kindly to this dish as it closely resembled 
Scotch oatmeal where meat broth was added. 

Samp, Hominy and Cornmeal. — Very early in the history of 
the colonial days, samp was placed upon the market. It was pre- 
pared by a purely mechanical method by which the hull and germ 
were separated out by a process of cracking and sifting. Samp 
is the edible part of the corn; it is practically the whole kernel 
minus the germ and hull. When coarsely ground it appears as 
hominy. The maize kernel was also ground between stones, 
bolted to remove the bran, and a meal thus produced which could 
be used directly as human food. Hominy or cornmeal could be 
boiled as hominy, mush or hasty pudding or baked as hoe-cake, 
johnny cakes, corn-bread and muffins. 

Modern Milling. — Modern milling operations have greatly 
changed the method of producing cornmeal and flour. Corn 
after being carefully cleaned is kiln dried to remove moisture, 
crushed between grooved mill-stones to desired fineness or ground 



JO FOOD INDUSTRIES 

between cylinders, and sifted to remove particles of bran. Not 
only is the outer bran removed much more carefully than in 
former years, but -to a large extent the germ also. This is par- 
ticularly true of flour meant for exportation, thus avoiding 
changes of a deleterious nature taking place during transporta- 
tion. In corn the greater part of the fat occurs in the germ 
which in time is apt to become rancid. The removal is, therefore, 
a distinct advantage as far as the keeping quality is concerned, 
but it greatly impairs the palatability and nutritive value of the 
prepared meal. Dr. H. W. Wiley claims that "Refined Indian 
meal has lost three-fourths of its fat, a large proportion of its 
mineral matter and also a very considerable portion of its pro- 
tein, due to the separation of the bran which is extremely rich 
in protein and the germ which is rich in oil and protein." 

The color of cornmeal and flour depends on the color of the 
variety of corn used, white or yellow. It is coarse or fine accord- 
ing to the process employed in milling. 

Uses. — I. Food for Man. — Indian corn is the leading cereal of 
this country. It is grown in all kinds of soil and under favorable 
conditions produces a large yield. Maize is lower in protein than 
wheat and oats, but fully equal to other cereals in that respect 
and contains a larger proportion of fat than most of the grains. 
It is a food well adapted to those engaged in hard, manual labor, 
as it yields a comparatively high amount of energy. Throughout 
the country it is used as food, but more extensively in the South 
where Indian corn is served in some form daily at one or more 
meals. 

As a garden vegetable, it is raised in large quantities for the 
market to be eaten on the cob or boiled with beans as succotash. 
The canning of corn is an important industry in some states, 
especially Maine and New York. 

Popcorn is used largely throughout the states as a delicacy. 
It is a specially hard variety which has the property of the com- 
plete turning inside out of the kernel on the application of heat. 

Corn is also used as before stated, either cracked or crushed 
as hominy and finely ground, either bolted or unbolted as meal or 



FOOD INDUSTRIES 7 1 

flour. On account of the inability of the nitrogenous constituents 
to form gluten, corn flour cannot be utilized for bread-making 
unless it is mixed with a large proportion of wheat flour. 

II. As food for cattle, corn silage is extensively used as well 
as the green and dried grain. 

III. Cobs furnish a fuel and are also used in the manufacture 
of tobacco pipes. 

IV. On account of its porosity and its power of absorption, 
pith of corn is used in the construction of war vessels, compressed 
blocks of it being placed behind the outer armor, where in case 
of its being pierced during battle the water will be quickly 
absorbed. Pith is also used for making varnishes, gun-cotton 
and other explosives. 

V. The husks are used in many country places for the making 
of mattresses. 

VI. It is largely used in the preparation of alcohol and alco- 
holic beverages. 

VII. The kernel which contains the starch in comparatively 
large amounts furnishes the source of supply for most of the 
American Starch Industry. For further information on this 
subject see Chapter IX, Starch and Allied Industries. 

Adulteration. — Practically no adulteration of corn products has 
been found by the United States Department of Agriculture. 



\J 



RICE. 



Origin.— -Rice has been cultivated from times immemorial, but 
it is supposed to have originated from the wild variety. Mention 
is made of its cultivation in China as early as 2800 B. C. It is 
undoubtedly of Eastern origin, for we find it early appearing in 
India and Japan as a staple food and allusion is made to its use 
in the Talmud. It is supposed to have been introduced into 
Persia from Southern India and later carried by the Arabs into 
Spain. Although it was raised in Southern Europe in the fifteenth 
century it was not introduced into the United States until 1694 
when the captain of a sailing vessel from Madagascar presented 
a bag of "paddy" rice to a Charleston merchant. It soon became 
6 



J2 FOOD INDUSTRIES 

an important industry of South Carolina and continued as such 
until the breaking, out of the Civil War. i 

Geographical Distribution. — It is now grown extensively in 
India, China, Japan, Southern Europe and in our own Southern 
States, particularly the' South Atlantic and Gulf Section. Caro- 
lina produces the best rice, large amounts being also grown in 
Louisiana and Texas. 

Composition. — Rice is rich in starch, poor in protein, fat and 
mineral matter. In the East the deficiency of protein is supplied 
by the addition of leguminous plants, a combination of rice and 
legumes being a cheaper complete food than wheat and meat. 
South Carolina and Japanese rices are richer in fat and are, 
therefore, highly prized among rice eating nations. 

Cultivation. — Rice is the most extensively cultivated of the 
grains, furnishing the principal food cereal for over one-third 
of the human race. Where dense populations are dependent upon 
an annual crop, rice has been chosen wherever the climate per- 
mits, as it is the most prolific of all crops. It will grow best on 
soil ill adapted for any other grain. Sub-tropical rather than 
tropical climate gives the largest yield. It requires a moist soil 
artificially flooded at certain seasons. The fields are often 
so wet that workmen may sink to their knees. It grows most 
freely on lowlands, especially on land which can be flooded, but 
it can also be raised on upland fields. Japan grows large quan- 
tities of rice on terraces of hills and mountain sides by flooding 
from reservoirs built on a higher elevation. 

Milling. — Primitive methods for milling rice were very simple 
and are still in common use in many of the oriental countries. 
Rough rice was placed in a hollow stone and pounded with a 
pestle until the hull and cuticle were sufficiently loosened to be 
removed by the process of winnowing. A hollow block of wood 
was afterwards substituted for the stone, a wooden pestle or 
pounder as it was called being so arranged above the block that 
the pounder would fall into the rice tub when operated by the 
miller. Water power in time was used and finally modern 
machinery and methods were introduced. 



FOOD INDUSTRIES 73 

The object of modern milling is to produce from rough or 
"paddy" rice, a rice for the market which has been not only thor- 
oughly cleaned and the husk and cuticle removed, but having 
the inner surface polished. To accomplish this, rice must pass 
through a long and complicated process. 

I. Rough rice is screened to remove dirt and foreign material 
of all kinds. 

II. Chaff is loosened by rapidly revolving mill-stones and 
removed by screening. This sifting also causes a separation of 
whole and broken grains. 

III. The outer skin is removed by pounding in a huge mortar 
with a pestle. By screening a separation is made of the clean 
rice and flour. 

IV. The clean rice has become heated through friction so must 
remain in cooling bins for 8 or 9 hours. After passing through 
brush screens to remove the last of the rice flour, rice is ready 
for the final process of polishing. 

V. Polishing is done by friction with moosehide or sheepskin. 
This process gives to rice its pearly appearance and satisfies the 
demands of fashion. It is a blunder, however, from the stand- 
point of food value as much nourishment is lost in the removal 
of nearly all of the fat during the polishing process. Unpolished 
rice is more economical, has greater food value and has a richer 
taste which makes the rice served in oriental countries so much 
superior to the grain here. 

Adulteration. — The adulteration of rice is confined to coating 
the grains with paraffin, talc or glucose. The object is to give 
a better appearance to the grain and protect it from insects. 

Uses. — I. Rice as a food furnishes a starch supply which is 
easily digested and is useful in disordered conditions of the di- 
gestive tract when many solid foods cannot be borne. In rice- 
growing countries it is used as a substitute for wheat bread and 
potatoes. Rice flour cannot be used for bread-making and is 
seldom used for cake but mixed with wheat-flour it gives white- 
ness to bread. 

II. A large proportion of the rice taken to Europe is used 



74 FOOD INDUSTRIES 

for starch-making, rice starch being used in laundries and mus- 
lin factories. 

III. It is the source of a drinking spirit in India and the 
national beverage of Japan is prepared from the grain by means 
of a ferment. In both Europe and America rice is used by the 
distillers of alcohol and it is often employed in beer-making. 

IV. Rice straw is used as a cattle food and as a material for 
bonnets. 

V. Rice polish or the fine flour resulting from the polishing 
process is utilized as a food stock especially for cows and pigs. 

VI. Rice hulls are used as fertilizers and also for packing 
around breakable articles. 

OATS. 

Oats furnish a more important food material for human be- 
ings in Europe than in America, the largest amount being con- 
sumed in the British Isles. Their chief use, however, both 
abroad and here is for cattle food especially for horses. The 
plant furnishes green forage, hay and straw as well as the milling 
products. 

Composition. — Unlike rice, oats are particularly rich in nitro- 
genous constituents and mineral matter. They are highly es- 
teemed as a food for the building and restoration of tissue. Oats 
contain more fat than any other cereal closely resembling Indian 
corn in this respect. 

Oatmeal. — As a human food, oats appear on the market as 
oatmeal or "groats." Many varieties are cultivated for the prepa- 
ration of oatmeal but in general character they bear a close 
resemblance to one another. The outer husk is closely adherent 
to the grain and cannot be entirely separated from the kernel by 
the ordinary method of grinding. Old fashioned oatmeal, there- 
fore, consisted of not only the kernel but a great deal of cellu- 
lose in the form of small, sharp particles. These acted as a 
stimulant to the intestines, irritating to some people. 

On account of the large amount of fat, oatmeal is often spoken 
of as a "heating food" and its use is discouraged during the 
summer months. In the American diet, however, oatmeal is 



FOOD INDUSTRIES 75 

not eaten often or in large amounts so this cannot be a serious 
consideration. Oatmeal is probably the most nutritious of the 
cereal foods, but it seems to have a peculiar heating effect on 
some people, causing skin eruption. The cause of this is not cer- 
tain, some claiming it to be caused by the protein, others attribu- 
ting it to a special constituent found in oatmeal. 

Milling. — In the manufacture the grain is thoroughly cleaned 
to remove foreign material of all kinds, kiln-dried to loosen 
the outer husk and to develop flavor, then screened to remove 
husks. The kernel thus freed is called groats. All forms of 
oatmeal are produced from these groats. For further informa- 
tion see Chapter VI. Breakfast Foods. 

Adulteration. — The adulteration of oatmeal is not frequent, as 
the price of this cereal is so low that the substitution of other 
grains would not be profitable. 

BARLEY. 

Origin. — Barley is generally supposed to have originated from 
the wild species native to Western Asia. According to Pliny 
it is one of the earliest of cereals in the diet of mankind. It has 
been found in the lake dwellings of Switzerland, in deposits be- 
longing to the Stone Age and in the earliest Egyptian monuments. 
It is spoken of in the Books of Moses and early Greek and 
Roman writers make many references to it. The Greeks are 
supposed to have trained their athletes on this cereal and the 
' sacred barley of antiquity figured on many of the ancient coins. 

Cultivation. — The cultivation of barley is somewhat similar to 
that of wheat so far as soil is concerned. It is, however, con- 
sidered the most hardy of all the cereal grains, its limit extend- 
ing farther north than the others and reaching as far south as the 
sub-tropics. It has been grown successfully in Ireland, Norway 
and Alaska and in Egypt, India and Algeria. 

Composition. — Barley contains all the nutritive properties of 
the other cereals. It contains less protein and carbohydrate than 
wheat, but has more fat and mineral matter. 

Use. — Until comparatively recent years, barley formed an im- 
portant article of diet in most of the northern countries and it 



y6 FOOD INDUSTRIES 

is still largely used in Northern Europe among the peasantry. 
In England it was the leading cereal of the early days, the tra- 
ditional goose-pie and bag-pudding of the Christmas feast being 
made of this cereal. It was used until very recently by 90 per 
cent, of the laboring class, but wheat has gradually taken its 
place throughout Great Britain although barley cakes are still to 
some extent eaten. 

. In Japan rice is generally supposed to be the only cereal, but 
barley is largely used among the poorer classes, a social line be- 
ing drawn between the rice-eating and barley eating natives. It 
is also much used among the Hebrews as a breakfast food and 
pudding. \ ■ 

Medically barley is rated as the mildest of the cereals and in 
various forms it is found often in invalid dietaries. 

In the Old World it is grown extensively for horses, cattle 
and pigs, the hay and straw being utilized. In the United States 
it is grown in the northern and western parts to some extent for 
hay, but its chief use is for making fermented beverages. It is 
not utilized to any extent as a human food, although it is some- 
times used in domestic cookery as an ingredient of soups and 
broths. 

Mill Products. — About the only products milled are meal and 
pearl barley. Barley meal is the whole grain cleaned, deprived 
of its outer husk and ground. In this form it is sometimes sold 
to the manufacturer of beer. Pearl barley has the outer and 
inner husk removed, is ground to a round form and put through 
a polishing process. As a food it is used mostly in this form for 
thickening soups, making cool drink for invalids and for infant 
feeding. 



CHAPTER VI. 



BREAKFAST FOODS AND COFFEE SUBSTITUTES. 

A canvass of our markets would reveal to-day an endless 
variety of cereals listed under the name of breakfast foods. In 
the early days of America, the only cereals utilized to* any extent 
were wheat as wheat flour and corn as samp, hominy, cornmeal 
and hulled corn. In New England the custom prevailed of using 
popcorn as a breakfast food. Bread crumbs were also fre- 
quently toasted and. used for that purpose. Oatmeal was later 
introduced by the Irish and Scotch immigration and finally bar- 
ley, rye and rice, but their use has always been more or less lim- 
ited to the foreign born population. 

It was not until the latter part of the 19th century that a new 
interest was awakened in this class of foods. Much experi- 
menting was done on the cereals, new methods of manufacture 
were developed and many new products were placed on the mar- 
ket listed under the name of "The Cereal Breakfast Foods." 
Probably no class of foods has ever been so extensively and in- 
geniously advertised. In a comparatively short time a bewild- 
ering variety could be purchased in the local markets; many ap- 
peared to remain indefinitely, but a far larger number soon could 
be found only in forgotten places. This constant and ever in- 
creasing variety of breakfast foods is giving to the cereals an 
important place in the dietary which was not known in the past 
history of our country. 

Classification. — Although the list of these foods is so long and 
varied, they fall very readily into four classes. 
/Whole grain. 
I. Uncooked<^ 

^Part of grain. 
II. Partly cooked. 

III. Cooked. 

IV. Malted. 

The grains commonly used in this country are oats, wheat, 
corn and to some extent barley and rice. In the majority of 



78 FOOD INDUSTRIES 

breakfast foods, only one variety of grain appears, at other times 
two or more are mixed. Breakfast foods are prepared directly 
from these cereals, either by mechanical manipulation, culinary 
processes or malting. Many times such changes are brought 
about in order to make the product ready either for immediate 
consumption or for serving after a moderate amount of cook- 
ing. These changes in composition usually consist in the more 
or less complete rupturing of the starch granule and sometimes 
bring about its conversion into more soluble forms. Other sub- 
stances of the nature of condiments are often added as maple- 
sugar, cane sugar and salt. Particular methods of preparation 
are usually trade secrets. 

I. Uncooked. — The whole grain variety is best represented by 
oatmeal. This is practically the old-fashioned cereal with mod- 
ern methods of preparation. Ingenious devices have been in- 
vented for the removal of foreign seeds, dirt and other sub- 
stances of an undesirable nature. The roller process is now used 
instead of the old idea of crushing but the roller is supposed only 
to take off the outer husks. They are removed now quite thor- 
oughly so the amount of cellulose left is much smaller than for- 
merly. Sometimes there is a gradual reduction of the kernel so 
oatmeal may be in the granulated form. This is more common 
in Canada than in the United States. 

Varieties consisting of parts of grain may be found in farina 
and cream of wheat. They are prepared from the hard, granu- 
lated particles of wheat usually taken from the first or second 
break in the manufacture of flour. It is the part of wheat from 
which patent flour is made. This class of breakfast foods is 
usually made from hard spring wheat as soft winter wheat is apt 
to break down too finely. 

The uncooked cereals are sold at a lower price as there has 
been less manipulation by the manufacturer. They require, 
however, a longer cooking in the home. 

II. Partly Cooked. — By far the largest number of the break- 
fast foods of to-day belong to this class ; 90 per cent, of the oat- 
meal consumed in the United States is in this form, on account 



FOOD INDUSTRIES 79 

of its easy preparation in the home. The first of these cereals 
to be introduced was the rolled oats. The preliminary treat- 
ment of cleaning; kiln-drying and hulling is practically the same 
as with the uncooked varieties. The "groats" then pass through 
a process of steaming and while still wet go to heated rolls 
which flatten them into flakes. Additional cleaning processes 
are sometimes used to loosen and remove the fine particles of 
floury matter before the flakes are put into packages. Almost 
all of the grains are now being flaked, while peas and beans are 
also found in the Canadian market. 

Originally this process of steaming was thought to cook the 
grain so thoroughly that only a few minutes were necessary in 
the home. It is now known that the heat has not been applied 
long enough and such cereals need to be thoroughly recooked 
before serving. Less water is needed as much has been absorbed 
in the steaming process. On account of the flattened condition 
of the grain exposing more surface it is not necessary to give as 
long a time as in uncooked cereals. More time, however, should 
be allowed than is stated on the package. 

III. Cooked. — The ready to serve varieties are numerous and 
are prepared in various ways. The most common forms are: 

i. The flaked cereals closely resembling the rolled variety, but 
heat has been continued for a longer time. They sometimes con- 
sist of one cereal as flaked rice or they may be combinations of 
grain as wheat and barley. Other substances such as syrup and 
salt are frequently added and some flaked varieties have passed 
through an additional process of parching or toasting, thus giv- 
ing them a darker color and producing a flavor which is relished 
by most people. Several of these flaked varieties as Cranose 
Flakes and Force were patented at Battle Creek, Michigan, the 
center for the development of breakfast foods, and were among 
the earliest of the ready-to-eat foods. 

2. The puffed variety, as Puffed Rice, is made by placing the 
grain in sealed cylinders which are kept revolving at a tempera- 
ture of approximately 550 F. for an hour. The moisture within 
the grain turns to steam, which on being released suddenly from 



CO FOOD INDUSTRIES 

the cylinders causes an explosion of the starch granule and a 
purling up of the cereal grain. 

3. There is but one example of the shredded variety, but so 
popular is it among Americans that it stands in a class by itself. 
"Shredded Wheat Biscuit" as it is called, was the first breakfast 
food to appear on the market made from wheat. Its manufac- 
ture dates from 1895. The whole wheat kernel appears in the 
product and special machinery is needed for its preparation. 
After a thorough cleaning the cereal passes through some 
twenty to twenty-five different processes, the most important of 
which are the following: 1st. the whole wheat is steam-cooked 
for about thirty-five minutes without being flavored then dried 
to remove excessive moisture; 2nd. by special machinery the 
grains are drawn into shreds which are piled in layers, cut into 
miniature loaves and baked. 

4. Variety resembling crumbs, as Grape-Nuts. This break- 
fast food is prepared from wheat and barley ground together, 
made into a flour, kneaded into bread dough and baked. The 
bread is then toasted and crushed. Grape-Nuts has had a very 
large sale in the United States, Canada and England for a num- 
ber of years and is now gradually being introduced in the com- 
mercial centers of foreign lands. 

IV. Malted Preparations.- — The cereal grains are all rich in 
starch and on account of the hard impervious nature of the walls 
of the starch granules such food is not easy of digestion in the 
raw state. A long slow cooking is necessary not only to rupture the 
granule, but to make the starch more soluble. The digestive 
fluids under ordinary conditions can then readily take care of 
such a product. To further aid digestion it was suggested sev- 
eral years ago that the cereal starch be subjected to the action of 
malt. Malt contains an enzyme called diastase which has the 
power of rapidly liquifying starch after the cell walls have been 
ruptured and then converting it into dextrin and maltose. Mal- 
tose is soluble and several steps nearer the completion of the di- 
gestive process. The amount of starch which has been changed 
to dextrin and maltose depends upon the thoroughness with 



FOOD INDUSTRIES 8 1 

which the malting process has been conducted. Manufacturers 
of these products claim that the process has been thorough and 
these cereals are highly recommended for people with weak di- 
gestion. It is a question whether this claim is always true or 
whether malt has simply been added to give flavor after the 
cereal has been cooked with dry heat. Heat would readily 
change starch to dextrin without the aid of diastase and is a 
much quicker process than that of malting. For information as 
to the malting process see Chapter XI, Alcoholic Beverages. 
Such a cereal has a pleasant taste relished by many people and 
adds variety to the diet, but it is not predigested. 

Experiments along this line have been carried out at the 
Iowa Experiment Station on a number of malted breakfast 
foods. It is difficult, however, to decide whether the malting 
process has actually been carried out or whether malt has been 
added, but there are strong evidences to make scientific men 
feel that in many cases the cereal has been cooked by dry heat. 
The term malted is often used when malt has simply been added, 
as malted milk. Milk cannot be malted in the sense of adding 
diastase to it; it can only be reduced to the powdered form then 
mixed with ground barley malt. Much has been said of the ad- 
vantage of using predigested foods in order to relieve the diges- 
tive tract of much of its normal work. It is a question, how- 
ever, as to the wisdom of taking habitually artificially digested 
foods. The human body under normal conditions is well fitted 
to perform this work for itself and the digestive organs need a 
certain amount of exercise to keep them in proper condition. It 
has often been quoted "A well man has no more need of predi- 
gested food than a sound man has of crutches." These cereals, 
therefore, should be taken more for their pleasant taste and to 
give variety than for their so called predigested value. 

Adulteration. — While in advertising much has been said greatly 
over-estimating the virtues of the breakfast foods, the experi- 
ment stations and pure food examiners have discovered very 
little adulteration. Manufacturers as a rule use good whole- 
some material, processes are modern and conditions at the fac- 



82 FOOD INDUSTRIES 

tories most sanitary. Goods are protected while in the dealers' 
hands and are so packed that they can easily be taken care of by 
the householder. 

Comparison of Old and New Cereals. — The old-fashioned cereals 
were much more economical. Manufacturers did not charge for 
extra manipulation. They were bought when dry, so consumer 
was not paying for water which had been added during manu- 
facturing processes, and as they appeared on the market in bulk 
the box was not included in the weight. 

Uncooked cereals which have been thoroughly cooked in the 
home digest just as easily as predigested kinds and are equally 
nutritious. In these respects they are superior to some varie- 
ties of partly cooked. There is no reason to believe that a pre- 
pared food is more favorable to health than cereal itself prop- 
erly cooked. 

On the other hand, much can be said in favor of the use of 
prepared breakfast foods for they are usually palatable, whole- 
some and nutritious. They save much time, labor and fuel in 
the home and are well suited for the use of the housekeeper, who 
must depend upon the use of kerosene, gas or electric stove. 
From a sanitary standpoint there has been a great improvement; 
being sold in cardboard boxes well lined with air-tight paper, 
they are protected from air, moisture, dust and micro-organism. 
Unless carefully packed a cereal will not keep well. Moist cli- 
mate makes it liable to be attacked by mold growth and it is apt 
to become infested with insects. The chief point against the 
modern cereal is the excess cost. The cost of cereal per pound 
is 2 to 3 cents; cost of prepared cereals io to 15 cents. The 
cereals, nevertheless, pound for pound, are the cheapest com- 
plete food that can be found on the market and they form a legit- 
imate and valuable food. 

COFFEE SUBSTITUTES. 

For several years past another cereal product has been found 
on the market known under the name of coffee substitutes. 
They are in many cases put up by the same manufacturers as 
the breakfast foods and like them seem to be gradually increas- 



FOOD INDUSTRIES 83 

ing in number. They are as a rule made of parched grains of 
wheat and barley sometimes mixed with wheat middlings, pea- 
hulls and molasses. Some of the first products also contained a 
low grade coffee added to give flavor. Experiments made at the 
Connecticut Experiment Station, however, show that the present 
day coffee substitutes are as a rule made from the cereal grain 
as claimed by the manufacturers and that there is now very little 
adulteration of this kind. 

It is claimed that they are harmless, unstimulating, have a 
flavor resembling coffee and yield much greater nourishment at 
lower cost. The color and flavor resembling coffee are largely 
due to the fact that the carbohydrates present are caramelized ; 
this also occurs in the roasting of coffee. See Chapter XX, Tea, 
Coffee and Coco. Few coffee lovers will agree that the flavor 
strongly resembles coffee as the coffee bean also contains certain 
volatile bodies which give that beverage the much desired aroma 
and taste. Substitute coffee where coffee has not been added 
is perfectly harmless, unstimulating, and furnishes a beverage 
for those who cannot take coffee. There is little truth, however, 
in the extravagent claims made in advertising matter as to the 
nutritive value of the beverage. This value is hardly worth 
considering, since experiments have shown that skim milk is 
from three to twenty times as nutritious. 



CHAPTER VII. 



UTILIZATION OF FLOUR. BREADMAKINa. 

By far the oldest and most important product made from flour 
is bread. The art of breadmaking dates back to the remotest 
ages of mankind and so important is this world's food-stuff that 
it is known almost universally as "The staff of life." With the 
possible exception of milk and eggs, there is no article of the 
diet that is more generally used by human beings and that is so 
well able to sustain life. It is to its constant use that we owe 
the wonderful development along the lines of the cultivation of 
wheat and the equally marked progress found in its milling oper- 
ations. 

In a broad sense bread includes all forms of baked flour, 
whether leavened or unleavened, but our common use of the 
word refers only to those forms in which leavening agents are 
used, other products being spoken of as pilot bread, crackers, 
passover bread and biscuit. Originally all bread was eaten with- 
out leaven for the savage after crushing or grinding his meal, 
baked it in the ashes of his camp fire. The result was a bread 
of hard, tough material not easy for the digestive fluids to act 
upon. This evidently was only the custom among the most 
primitive people, for the use of leaven is very ancient. The 
Israelites while in Egypt used leavened bread, the Greeks were 
known to have cultivated the yeast plant and in the ruins of 
Pompeii an oven was found containing 81 loaves of bread not 
unlike our own. With the use of leaven, a type of bread was 
produced, more easily masticated, better in flavor and more 
easily digested. 

Primitive Breadmaking. — Crude methods of breadmaking can 
be studied not only by the earliest historic records but among 
some of the more primitive nations of to-day. Evidently bread 
was used in the stone age for burnt specimens have been re- 
covered among the Swiss Lake Dwellers ; the pyramids of Egypt 
bare testimony to its early use and again we find evidences of it 
in the mound tombs of North Africa and Asia. The method of 



FOOD INDUSTRIES 85 

preparation was undoubtedly very simple, probably much like 
that used by some of the wild tribes that inhabit parts of Africa 
at the present tirhe. It is their custom to simply grind grain be- 
tween two stones, make it into a paste with water, then bake it in 
the ashes of a camp fire. 

In different parts of the world similar products can be found. 
Natives of some of the West Indies prepare a thin round cake 
of meal which is obtained from the cassava root; it is known as 
cassava bread and furnishes the principal food among the com- 
mon people. In Mexico and Central America, a bread known as 
"tortillas" is prepared by the natives from Indian corn by first 
parboiling the grain to soften it, then crushing it by means of a 
stone rolling pin. The paste is baked on a plate of iron. The 
"tortillas" is sold at many of the market places by native women 
and as it is more highly relished when served hot, it is usually 
baked on a small portable, charcoal stove at the market. Among 
the well-to-do classes of India, a round, flat cake of unleavened 
bread called "chapatties" is prepared from wheat flour and 
baked on a griddle or on the coals. A similar product is made 
by the poorer classes from cornmeal, millet, barley or a coarse, 
hard grain known as raggy. In Palestine and Syria women are 
still the millers and bakers, grinding the meal in small stone 
hand-mills after the same custom as was used long before the 
beginning of the Christian era. The coarse meal obtained is 
made into flat cakes and baked on a hearth, which consists of 
two stones raised on end over which an iron plate is laid to hold 
the bread. Bread made in other parts of the Orient as Egypt 
and Turkey has quite a different appearance. Here the material 
is rolled or pounded into a flat dough similar to our pie crust; 
two layers are then put together united at the edges and baked 
in a very hot oven. The expansion of the air between these 
layers puffs up the dough and gives the appearance of a large 
loaf. A flat bread of coarse barley meal is also made in the 
northern part of Europe, particularly among the Norwegian 
peasants. 

The evolution from these primitive breads to the modern white 



86 FOOD INDUSTRIES 

loaf used by the civilized world has needed much study and ex- 
perimentation as in the development of all other industries. 
Probably the most marked change was the use of leaven and it is 
generally supposed that it is to the Egyptians that the world 
owes this important step. They seemed to have carried the art 
of breadmaking to a high state of perfection, as did also the 
ancient Greeks, who are known to have had at least 62 varieties 
of bread. From the days of these ancient civilizations, mechan- 
ically there seemed to be little progress for centuries and it has 
been left to the modern scientist to develop the art and science 
of breadmaking. 

Leavened Bread. — So far as the ingredients are concerned, the 
present day bread might be considered a very simple food, for 
there are only four materials needed in this operation — flour, 
water, yeast and salt. Other materials as butter, lard, sugar, 
milk, fruit or spices might be added to give flavor and variety, 
but they are not essential to breadmaking. Although the in- 
gredients are so simple, scientists tell us that the chemical 
changes taking place in the preparation of the loaf are very pro- 
found. In order to understand at least a small part of these 
changes it is necessary to consider the raw material to be used. 

Flour. — At the present time our first-class bakers are using a 
standard flour for breadmaking. It is high in the gluten form- 
ing proteins so will absorb more water and gives a larger, lighter 
and better flavored loaf. For milling processes see Chapter IV. 

Water. — The hardness or softness of water does not seem to 
make any great difference in breadmaking. but it should be free 
from dirt or contamination of any kind. See Chapter II. Water. 
In the household many prefer to use milk in part or altogether 
as the liquid. It makes an equally light loaf, contains a larger 
amount of protein and fat, is equally digestible, but the dough is 
slightly longer in rising. 

Salt. — Salt is used in breadmaking principally for the flavor 
it imparts, for without it the dough would be insipid. The 
amount varies according to the type bread and in different locali- 
ties even with the same varietv. It should never be used, how- 



FOOD INDUSTRIES 87 

ever, in such quantities as to be readily tasted or the delicate 
aroma and taste of the bread will be destroyed. It is believed 
that salt added in small quantity stimulates the capacity of the 
palate for recognizing flavors of other substances. This accounts 
for the importance of salt as a flavoring agent. 

Another reason has been given for the use of salt, but it is 
not now believed to be important. It has the power of control- 
ling some of the chemical changes which take place during fer- 
mentation, so was considered a preservative. It checks alcoholic 
fermentation and also the ropy ferment, but it does not influence 
the lactic acid and many other bacteria from working so its 
influence as a preserving agent is very limited and can hardly be 
important enough to be considered. 

Yeast. — Yeast was the first leavening agent in the world's his- 
tory and is still by far the most important one. How it first 
came to be used is not told us in history, but the knowledge that 
wild yeast is always present in the atmosphere leaves but little 
to the imagination. Its use might easily have been discovered 
by accidentally exposing dough to the atmosphere and after- 
wards finding that it made a lighter loaf. From this simple 
custom of exposing dough to the air we might easily trace the 
practice of saving a small amount of raised dough from day to 
day to act as a leavening agent for the next baking. Gradually 
the art of cultivating yeast became the practice among the civil- 
ized nations. 

Although yeast has been used as a leavening agent for many 
centuries very little was really known about it until the time of 
Pasteur. It is now believed that yeast, molds and bacteria 
belong to a class of substances known as ferments. Until 
quite recently these ferments were divided into two classes : 
1st, enzymes, such as diastase and ptyalin or unorganized fer- 
ments ; 2nd yeast, molds and bacteria, known as organized fer- 
ments. Recent research has revealed that micro-organisms can- 
not do their work as ferments without the presence of enzymes 
within their cell-walls so that classification no longer can be used. 
Yeast, molds and bacteria are now known to be living organisms. 
7 



88 FOOD INDUSTRIES 

They are microscopic forms of plant life which in their desire 
for food can act upon substances, bringing about many profound 
changes. Although the nature of these changes may not be 
known to the average house-wife, with the effects of many she 
is quite familiar. Milk after standing for a time, particularly 
in a warm place changes in its nature; it develops acid qualities 
and is spoken of as being sour. Butter under certain conditions 
becomes rancid. Cider when fresh has a decidedly sweet taste 
which in time gradually disappears and is replaced by an unmis- 
takable taste of alcohol. It is quite common to speak of this 
product as hard cider and every house-keeper knows that should 
hard cider be kept long enough it will change to vinegar. These 
changes and many others modern scientists have traced to the 
fermentative actions of micro-organisms. 

In the fermentation brought about by the yeast plant two very 
important products are found, alcohol and carbon dioxide, which 
are used throughout the world whether the races are civilized or 
still in a semi-barbarous condition. Alcohol is particularly de- 
sired by all industries preparing stimulating beverages and car- 
bon dioxide is needed for the lightening of bread. It is to the 
manufacturer of alcoholic beverages that we owe the scientific 
study that has been given to the yeast plant. 

When viewed through a microscope yeast is found to consist 
of a single cell round or oval in shape. It is perfectly colorless, 
belonging to a class of plants without chlorophyll- — the fungi. 
Each cell is an individual plant consisting of an outer wall of 
•cellulose filled with protoplasm. In this condition yeast is usually 
spoken of as in the resting state. , 

Being a living organism yeast is capable of reproducing itself 
should conditions be favorable. The normal reproduction is 
through a process of budding. If a little of this resting yeast is 
put under- conditions favorable for growth, a daughter cell or 
bud is formed within the cell. The bud pushing its way through 
the wall rapidly develops, separates from the parent cell, and in 
its turn is able to become a parent cell. When growth is very 
rapid the cells sometimes fail to separate, and adhering, form a 



FOOD INDUSTRIES 89 

chain of cells which can easily be seen in the microscope. Pas- 
teur states that on one occasion he watched two cells for two 
hours; during that time they multiplied into eight. 

Under unfavorable conditions some yeasts are reproduced by 
the formation of spores. These spores can resist many adverse 
circumstances, such as lack of moisture, insufficient food and 
marked changes in temperature. It is to their hardy nature that 
we owe the constant presence of yeast in the atmosphere. In 
this state it has been discovered yeast can live in the ground for 
some little time, until wind carrying them into the air, gives an 
opportunity for settling amid favorable surroundings and again 
growth and reproduction take place. The favorite home for the 
yeast plant is on the skin of grapes and other fruit, a fact well 
appreciated by those engaged in the wine industry. 

The rapidity of the growth is much influenced by surrounding 
the yeast with favorable conditions of temperature, suitable food, 
oxygen and moisture. 

The temperature found to be most favorable is 77°-95° F. 
Below yy° F. the growth is slower and a little below 49 F. it is 
practically arrested. The vitality of the cell is not destroyed by 
a low temperature for even after exposure to 32 F. yeast will 
grow if the conditions are once more favorable. Above 95 ° F. 
yeast will become gradually weakened by heat until it is finally 
killed at a temperature of 140 F. if the yeast is moist. Dry yeast 
can stand a much higher temperature, 200 F., without destroying 
life. Although yeast grows most rapidly between 77°-95° F. 
it is sometimes advisable to keep the temperature lower to pre- 
vent the action of undesirable micro-organisms. Brewers in the 
United States and on the continent are now using a lower tem- 
perature although none but the largest and more scientific bakers 
seldom, if ever, take advantage of this fact. 

Food for yeast growth must contain carbohydrate, nitrogenous 
compounds and appropriate inorganic matter. The last two 
food principles are necessary for the healthy development of 
yeast for they constitute, as in human life, the building material 
of the cells. 



90 FOOD INDUSTRIES 

Pasteur discovered that unless these substances are given to 
yeast they act like cannibals, the stronger cells existing on the 
weaker. From our standpoint the carbohydrate is the most im- 
portant food for the yeast as it is to these compounds that we 
look for the production of alcohol and carbon-dioxide. All 
forms of carbohydrate cannot be utilized by yeast but should the 
compound not be available as food, yeast carries its own enzyme, 
much as we do, which can convert it into a form which can be 
utilized. There are two important enzymes in yeast — invertase 
and zymase. The function of invertase is to convert such com- 
pounds as starch and dextrin into glucose by the process of 
hydrolysis : 

(C 6 H ]0 O 5 )« + H 2 — C 6 H 12 6 . 

Glucose being an available food for yeast it is attacked by 
zymase which breaks down the sugar into alcohol, carbon dioxide 
and a number of other substances in small quantities such as 
fusel oils, succinic acid and glycerine. 

C 6 H 12 6 — 2C 2 H 5 OH + 2 C0 2 . 

Micro-organisms also need oxygen, some taking it in the form 
of atmospheric oxygen 2 arid others from their food. Yeast 
needs atmospheric oxygen. Pasteur discovered that an abund- 
ance of air caused the plant to develop rapidly, but the evolu- 
tion of alcohol and carbon dioxide was very slow, while in a 
limited amount of oxygen fermentation proceeded rapidly and 
the cell growth was arrested. This idea has been of great bene- 
fit to brewers and to scientific bread bakers who now know when 
to limit the supply of oxygen. 

Yeast needs also for development a certain amount of moist- 
ure. In fact one of the largest and best known breadmaking 
concerns in the United States make their bread under a process 
patent, based on the idea of mixing the dough in such a manner 
as to inject into the dough an unusual amount of atmospheric 
oxygen. 

Leavening Effect of Yeast. — With these facts in mind the 
leavening effect of yeast can easily be seen. A mixture of flour 
and water readily supplies the moisture and food, flour con- 



FOOD INDUSTRIES 9 1 

taining all the necessary compounds — carbohydrate, protein and 
mineral matter. If this material be kept exposed to the atmos- 
phere and at a suitable temperature, yeast will multiply very rap- 
idly and will spread throughout the dough. As a result of its 
action much carbon dioxide is developed, which in forcing its 
way through the dough becomes entangled in the gluten. The 
latter being elastic stretches, thus giving porosity and lightness 
to the dough. 

Yeast Preparations — Breadmaking. — The oldest method of pre- 
paring yeast was very probably that used by the ancient Egypt- 
ians, who succeeded in obtaining wild yeast and growing it in 
dough. A portion of this dough or "leaven" was always saved for 
the next baking and as it contained yeast cells, again yeast could 
be grown when needed. This simple custom has been used more 
or less from those early days to modern times and in some parts 
of the world it is still practiced. The home brew used by our 
ancestors and which can still be found in isolated districts is a 
preparation of this kind. The leaven saved from the last baking 
is mixed with suitable material for the rapid growth of yeast. 
A decoction of hops or potatoes and water were used and when 
the yeast had developed, part of this material was added to the 
dough. A similar practice can be found in Scotland at the 
present time. The "barm" as it is called is prepared by allow- 
ing yeast to grow in malt extract and flour before adding it to the 
bread dough. In some parts of the continent this ancient method 
is still used by bakers and in many places by the poor country 
people, particularly in France and Switzerland. The bread has 
a sour taste due to the development of lactic and butyric acid 
bacteria, which is relished by many people. Some authorities 
consider bread made in this way more healthful as the acids 
developed are supposed to assist in digestion. The taste, how- 
ever, is disagreeable to the majority of people and the best au- 
thorities of our country consider that a high grade commercial 
yeast is more reliable and much more convenient. 

B reiver's Yeast.- — One of the earliest commercial yeasts was 
obtained from brewers. During the fermentation of beer, es- 



92 . FOOD INDUSTRIES 

pecially where a high temperature is used, much of the yeast is 
carried to the top of the vats by the escaping carbon dioxide. 
It is called by the brewer top yeast. This yeast was skimmed 
from the top of beer and was sold in the liquid form. Little 
care was given to sanitary conditions and the product was thor- 
oughly unreliable. It was dark in color and carried with it the 
flavor and aroma of the hops. Bread made from it was some- 
what smaller in volume, due to slow fermentation, dark in color 
and had a faintly bitter flavor. It has now almost entirely been 
superseded by distillers' yeast, which at the present time is sold in 
the form of the compressed yeast cake. 

Compressed Yeast Cake.- — Distiller's yeast is lighter in color 
and possesses a rather pleasant taste. At the time that fer- 
mentation is most energetic the yeast is skimmed off the surface 
and is conveyed by wooden drains to sieves. All foreign matter 
is removed and the strained liquid passes on to the settling cis- 
terns. Here the yeast settles and the liquid is drawn off. The 
yeast is generally mixed with starch and put into presses which 
squeeze out much of the moisture, leaving a dough-like paste. 
The starch is said to be added because it permits more water 
being removed, which greatly aids the keeping quality. In recent 
years, however, the foremost yeast manufacturers of our country 
have discovered that by strict laboratory control and the develop- 
ment of pure culture, compressed yeast of great strength and uni- 
form quality and flavor can be successfully and commercially 
made without the addition of starch. The latter, in fact, is now 
looked upon as an adulterant. Yeast is then partly dried, made 
into cakes, and carefully wrapped in metal or waxed paper to 
protect it from bacteria. This is the best all-around yeast that is 
used at the present time. It is more expensive, but will work 
evenly and quickly and will give a finished loaf of bread with a 
good volume and texture and having an agreeable taste, odor and 
color. A good quality should be slightly moist, possess a creamy 
white color and should break with a fine fracture. 

Dried Yeast. — There is one great disadvantage to compressed 
yeast ; even under favorable conditions it will only keep fresh 



FOOD INDUSTRIES 93 

for a comparatively short time. The yeast begins to die and other 
forms of micro-organisms begin to develop, giving rise to unde- 
sirable flavors in bread. For people who live in isolated dis- 
tricts, another type of compressed yeast called dried yeast is put 
on the market. More starch has been added and more water 
removed. Although a low temperature is used to dry the yeast 
some of the cells are undoubtedly killed, so it is not as satisfac- 
tory a form to use as a fresh yeast. On account of the dryness, 
however, decomposition cannot set in and some of the yeast and 
spores will remain alive for a considerable length of time, and 
when mixed with water and a soluble carbohydrate will slowly 
begin to grow. 

Object in Breadmaking. — Given the necessary ingredients, it is 
the baker's object to produce a result which will be pleasing to 
the sight, agreeable to the taste, easy of digestion and nutritious. 

Steps in Breadmaking. — i. Fermentation. — The methods of 
fermenting dough are somewhat varied, but there are only three 
in common use : 

I. Straight or off-hand dough. 
II. Ferment and dough. 

III. Sponge and dough. 

No matter which method is chosen the best material possible 
to procure should be used; the ingredients should be thoroughly 
mixed and in proper proportions, and the greatest cleanliness 
should be observed throughout the entire operation. 

I. Straight or Off-hand Dough. — With this method all of the 
ingredients while luke-warm are thoroughly mixed. Care should 
be taken that the proper proportions are used ; too little yeast will 
give a badly raised dough and too much will cause excessive gas 
which stretches the gluten beyond its limit, causes it to break open 
and the gas to escape, thus making a heavy, soggy loaf of bread. 
The dough is then set aside to rise in a moderately warm tem- 
perature (77°-95° F.). It should be kept as free from drafts 
as possible and should be left exposed to the atmosphere or 
lightly covered, as the presence of oxygen aids the growth of 
yeast. As fermentation proceeds the dough increases in bulk and 



94 FOOD INDUSTRIES 

becomes light and porous. When sufficiently aerated with gas 
it is thoroughly kneaded by hand or machinery. This operation 
causes the escape of waste gases, incorporates fresh air, revives 
the activity of the yeast, has a toughening effect on the gluten 
and assists its elasticity. The dough is shaped into loaves, 
allowed to ferment again and then baked. Bread made in this 
way takes from 3 to 10 hours according to the amount of yeast 
and the temperature used. There are several distinct advantages 
to this method — all labor of sponging and extra manipulation is 
saved and bread is produced in less time. It is far more con- 
venient when bread is made at home. 

II. Ferment and Dough. — Among many bakers the first step 
is the preparation of the ferment ; that is, the cultivation of the 
yeast by giving it appropriate food. Potato mash is still largely 
employed for food, also raw and scalded flour, malt extract and 
commercial yeast foods. The ferment takes about 5 hours, but 
is still used by bakers for two reasons : first, it enables an origin- 
ally small amount of yeast to do much work ; second, the young 
yeast cells are very vigorous. This yeast is then incorporated 
with water, flour and salt and a dough is made similar to the 
straight-dough method. 

III. The Sponge and Dough Method. — In this process the 
dough is made in two stages by allowing the yeast to work for a 
period in a portion of the flour and water. Several different 
sponges are used — the quarter, the third, the half and the three- 
quarter, according to the amount of flour added. Fermentation 
proceeds from 2 to 12 hours and the remaining material is incor- 
porated. Care should be given to mix the second portion of 
flour thoroughly with the sponge or the bread will contain lumps 
on which the yeast has had no opportunity to work. The dough 
as it is now called is allowed to rise again, is kneaded into loaves 
and baked. Although it takes longer and requires more manipu- 
lation the sponge method has many advantages : first, on account 
of its slackness, it requires much less yeast — this is a considerable 
saving where bread is made in large quantities ; second, hard 
wheat flour on account of its absorbing power does not produce 



FOOD INDUSTRIES 95 

a desirable loaf of bread when made by the off-hand method — a 
sponge gives a lighter and more elastic loaf; third, bread made 
with a sponge is usually finer in texture and has a better flavor; 
fourth, it keeps better; fifth, some believe that less work is 
involved in mixing as the sponge softens on standing. 

2. Baking. — The dough should be evenly baked in an oven 
ranging from 450 to 550 F. according to the variety of bread. 
The heat should not be too great at first or the bread will harden 
too quickly. The gas in the interior will not have a chance to 
expand the gluten and the result will be a heavy bread. In some 
bakeries the temperature is gradually raised during baking. The 
effect of this heat is to rapidly expand the gas which in its turn 
expands the gluten and swells the loaf. As gluten is protein in 
nature it very shortly coagulates and thus holds the loaf in shape 
after the escape of the gases. The surplus moisture, the alcohol 
and acids volatilize. In time the starch granules are ruptured 
and become suitable for human food. On the outer portion or 
crust on account of the intense heat, most of the starch is dex- 
trinized and a small portion is converted into glucose. The inner 
part or crumb is not subjected to as intense heat, since dough is 
not a good conductor of heat. The interior is not heated above 
the boiling point of water so the changes in the carbohydrate 
grow less as it approaches the center of the loaf. The yeast and 
bacteria are killed during baking and all enzymes present in the 
yeast and flour. This sterilizes the bread. 

3. Cooling. — As soon as completely baked, bread should be 
placed on sieves or bread-racks so that the air can circulate 
around them until they are thoroughly cool. This gives the gas 
and steam within the loaves an opportunity to escape and pre- 
vents the bread from becoming damp. 

A Modern Bread Factory. — In strong contrast to the old- 
fashioned cellar bakery with its dingy and many times insanitary 
surroundings, the modern bread factory has arisen. Here can 
be found bread being manufactured on a large scale in a well 
ventilated, sun-lighted building equipped with facilities as nearly 
perfect as modern science can suggest. An electric plant for 



96 



FOOD INDUSTRIES 



lighting the building and running the machinery, a cold storage 
plant and hot water system for regulating temperature, elevators, 
conveyors and slides for carrying material from one part of the 
building to another, can be seen. Many curious devices in 
machinery have been invented, so that the human hand needs 
scarcely to touch the product from the time that the raw materials 
enter the building until the finished loaf is ready to be carried 




Fig. 18 — Flour Sifter and Blender. 
(Courtesy of Ward Baking Co.) 



out for delivery. Conditions insuring thorough cleanliness are 
carefully sought and the bread is made amid thoroughly sanitary 
surroundings. Only a high grade flour, good yeast, distilled 
water and the best available material for shortening are used. 
Before being utilized the flour is passed through a sieve con- 
taining rotary brushes and a surprising amount of wood, lint, 
dust and other foreign material are removed. When needed, 



FOOD INDUSTRIES 



97 



the sifted flour passes automatically to electric bread mixers, as 
does also the required amount of water, dissolved yeast, salt, etc. 
As the bread mixer revolves, filtered air is fed to the dough in 
order to hasten the action of the yeast and give whiteness to the 
product. The mixing operation requires some 25 minutes. The 
mixer is then turned over and the dough drops into the raising 
trough, where it is allowed to rise in a sunny, white-tiled room 




Fig. 19.— Mixing Machine with Dough About to be Lowered Into Raising Trough. 
(Courtesy of Ward Baking Co.) 

for 3 hours. As soon as the dough is in proper condition, the 
bottom of the tub is removed and the dough proceeds by gravity 
through an opening in the floor to an apartment below, where it is 
automatically carried to a machine which weighs and cuts it into 
uniform pieces. It passes on a moving platform in separate 
loaves to a number of kneading devices which roll and press it 
into shape. The loaf travels forward and backward on a con- 



9§ 



FOOD INDUSTRIES 



veyor, where it is allowed to rest before it drops into a pan ready 
for the second rising. The pans are removed to an apartment 
heated to no° F., and the bread is allowed to rise. It is then 
baked at a temperature of 450-550 F. On being removed from 
the oven, the bread falls on racks from which place it proceeds 
on an incline to the floor below where after cooling, it is wrapped 
and sealed in paraffin paper. 




Fig. 20. — Machine for Dividing Dough Into Equal Parts of Equal Weight. 
(Courtesy of Ward Baking Co.) 

Souring and Its Prevention. — The souring of bread is due to 
the development of lactic and butyric acid ferments.. This may 
be caused by a poor grade of yeast which is apt to contain un- 
desirable bacteria ; by a poor flour which on account of the 
presence of certain nitrogenous bodies gives a medium particu- 
larly suitable for bacterial growth ; by dirty vessels ; by allowing 
the sponge to proceed too far thus giving the acetic ferment an 



FOOD INDUSTRIES 



99 



opportunity to develop. It may be prevented by using a high 
grade flour, a good yeast and by thorough cleanliness. Too high 
a temperature during fermentation and prolonged raising of the 
sponge and dough should be avoided. Sudden changes in tem- 
perature should be guarded against. 

Adulteration of Bread. — Alum has been largely used and evi- 
dently for a long period. English history speaks of Henry VIII 




Fig. 21 — Front View of Dough Divider. 
(Courtesy of Ward Baking Co.) 

ordering his baker to be hanged for using alum in bread intended 
for the King's table. This subject has been much discussed of 
late years and its use has been finally prohibited by the Pure 
Food Law. As a rule alum > was used with a poor grade flour 
or with a flour that had been kept for a long time under unfa- 
vorable conditions. When flour deteriorates the protein some- 
times changes, becoming more soluble and will not make a good 



IOO 



FOOD INDUSTRIES 



dough. Alum will cause it once more to become insoluble and a 
better gluten will he formed. The loaf is larger, less sodden, 
whiter and gives the appearance of a better grade flour. 

Losses in Fermentation. — In the preparation of bread by means 
of yeast, appreciable losses of dry material must necessarily take 
place. This is caused by the formation of volatile matter during 
fermentation, such as carbon dioxide, alcohol and acids. They 







Fig. 22.— Machine for Wrapping Bread with Paraffin Paper. 
(Courtesy of Ward Baking Co.) 



are driven off, to a large extent, at the temperature of baking, 
so have no nutritive effect. Estimates of this loss have been 
taken and as a rule it has been found to be approximately 2 per 
cent, although it may be much higher under unfavorable con- 
ditions. Liebig calculated that the loss in Germany daily would 
supply 400,000 persons with bread and it has been estimated that 
300,000 gallons of alcohol are annually wasted in the bakers' 



FOOD INDUSTRIES 



IOI 



ovens in London. There has been much experimenting and large 
sums of money expended in trying to recover this alcohol, but 
without success from the baker's standpoint ; the bread was 
found to be dry and unpalatable. This inevitable waste has led 
to attempts to convert dough into a porous form by other methods 
than that of fermentation. Many mechanical and chemical proc- 
esses of aerating dough with C0 2 have been invented, but in 




: V; ,,-:;,.,*» - 



Fig. 23.— Bread After Leaving Wrapping Machine. 
(Courtesy of Ward Baking Co.) 



England and the United States, only two have met a slight suc- 
cess. 

I. Chemical Process. — Use of baking powders. See Chapter 
VIII. 

II. Aerated Bread. — In this process water is saturated with 
C0 2 prepared by chemical reaction. This highly charged water 
is then mixed with flour under pressure in air-tight chambers. 



102 FOOD INDUSTRIES 

When the pressure is lowered the dough is forced out and blown 
up by the expanding gas. It is cut into loaves quickly and baked. 
This bread is very light, porous and involves no waste of ma- 
terial but unfortunately it has an insipid taste due to the absence 
of the by-products of yeast, so has never met with great success. 

THE CRACKER OR BISCUIT INDUSTRY. 

Those products formerly known in the United States as crack- 
ers and in England as biscuit originally included only varieties 
of unleavened bread, such as the commonly known pilot bread, 
ship's biscuits and water crackers, but the march of progress 
in the last half century has greatly enlarged the field of this 
industry until it now includes many articles formerly considered 
cakes, pastry and confectionery. 

In both this country and in England the manufacture of bis- 
cuit has been greatly improved and the output tremendously in- 
creased, one American firm alone manufacturing some four hun- 
dred or more different varieties. Great manufacturing concerns 
have been attracted by this field of business and have by their 
efforts to produce a perfect product brought about improvements 
resulting in cleanliness and sanitation in the manufacture of these 
products. The dirty and insanitary cracker bin and barrel of the 
grocery store, such as was fomerly used when crackers and bis- 
cuit were sold only in bulk form, the chance for the small dealer 
to deceive, the many varieties of cheap scales, and such numerous 
handlings as were necessary .to deliver the goods to the purchaser 
are all things of the past. The public now receives its biscuit 
in air-tight, moisture and dust-proof packages, packed and sold 
under the best possible conditions and free from the touch of 
human hands on their journey from the factory to the table of the 
consumer. 

Raw Material. — For the most part, flour made from winter 
wheat is used in the preparation of biscuit, although different 
varieties will contain Graham, whole wheat and cereal flours. 
Butter, lard and specially prepared, refined fats from vegetable 
sources shorten the goods, and pure water or high grade milk 
furnishes the moisture, while yeast, bi-carbonate of soda, baking 



FOOD INDUSTRIES 



IO3 



powder or aeration, assisted by the presence of eggs and fatty 
matter, serves as a leavening agent. There are many varieties of 
fancy biscuit in which are used refined sugar, fruits, spices, 
cheese, eggs, chocolate, nuts and confectionery. The ingredients, 
as above set forth, are carefully measured and weighed, then 
placed in a mixer, usually a large steel receptacle with revolving 
arms, and are thoroughly mixed by machinery for a definite 
time. If the leavening agent be yeast, a period of incubation at 
a properly fixed temperature must follow. The dough, now 




Fig. 24.— A Baking Floor showing Ovens. (Courtesy of The National Biscuit Co.) 



thoroughly mixed and having been allowed to rise the proper 
length of time, is wheeled in its clean steel car to the dough- 
breaks where, by being rolled and folded between great rollers, it 
is kneaded into the proper thinness and ready for the machine 
which further shapes and stamps it into the form in which it is 
baked with the design and trade mark impressed on the dough. 
The ovens used to bake biscuit are generally direct heat with 
8 



104 FOOD INDUSTRIES 

rotating shelves and are kept at a temperature approximating 
500° F. After being .baked and taken from the oven, the biscuits 
are cooled and immediately packed in their moisture and dust- 
proof packages, in which they start their journey, often the 
same day they are packed, to the ultimate consumer (Fig. 24). 

MACARONI. 

In the world's food products made from wheat, macaroni has 
occupied an important place in the diet of several nations. The 
Japanese claim to be the original manufacturers but whether this 
be true or not, the Europeans first heard of it from the Chinese 
who had been using it for a long period. Although the Germans 
were the European discoverers of macaroni, it was the Italians 
who early learned to appreciate its virtues and to adopt it as a 
national food. By the 14th century, Italy was the only European 
nation that understood its preparation, and for nearly four hun- 
dred years she held the secret of the method of manufacture. 

The Italian macaroni industry had its birth in Naples from 
whence it spread throughout Italy and finally to other parts of 
Europe, but it was not until the latter part of the 19th century 
that this product could be equaled in any other country. It was 
finally introduced into France where it has become an important 
industry. Although the United States is still a large importer of 
macaroni, there has been a great growth in the macaroni industry 
since the cultivation of durum wheat in our own northwestern 
states. 

In the preparation of macaroni a hard, very glutenous wheat 
is used, called macaroni wheat. The early Neapolitan manufac- 
turers won their fame on account of the excellent quality of the 
Italian wheat. Unfortunately the cultivation of native wheat 
is now sadly neglected in Italy. Russia for a long period' has 
produced some of the finest varieties. They were grown exten- 
sively for macaroni-making long before Liebig started his experi- 
mentation on hard wheat as a breadmaking material. Algerian 
durum wheat, the wild goose wheat. of Canada and Argentina 
macaroni wheat are also largely exported for this industry. 

Manufacturing Processes. — In the macaroni manufacture the 



FOOD INDUSTRIES IO5 

first step is the preparation of a coarse meal called "semolina" 
or "semola." Wheat is cleaned by steeping in water, dried by 
heat, ground and sifted. The husks and much of the starchy 
flour are separated out leaving the light amber, glutenous part 
resembling a meal rather than flour. As a rule manufacturers 
of macaroni buy their semola from millers, rather than do their 
own grinding. The best macaroni is made by blending various 
grades of semola much as flour is blended for breadmaking. 
The semola is then put into an iron mixer, moistened with the 
smallest possible quantity of hot water and thoroughly mixed 
by machinery for about 7 minutes or until the dough has a smooth 
and tough appearance. The mass is kneaded for a few minutes 
and is transferred to a cylinder. Pressure descends upon the 
dough, forcing it in strings slowly through the perforated plate 
which forms the bottom of the cylinder. The form of this plate 
fixes the character of the macaroni. If the holes contain a steel 
pin or conical blade the dough takes the- form of a pipe-stem and 
is known as tube macaroni. Holes without pins give solid mac- 
aroni and smaller holes produce spaghetti and vermicilli. A 
flat opening sometimes takes the place of a round hole and ribbon 
forms are made. When the strings of paste are the proper length 
they are cut either by hand or by automatic rotary knives. The 
macaroni is then thrown over reed poles to dry. When the 
weather is fine it is left exposed to the sunlight for about two 
hours. When partly dry, it is put into underground vaults and 
kept in this damp place for about 12 hours or until the dough 
has lost some of its brittleness and is once more pliable. The 
poles over which the macaroni hangs are then carried to store- 
houses where they remain until the strings have a horn-like tough- 
ness. They are now ready to be inspected, sorted, weighed and 
packed for shipment. In case of bad weather the macaroni is 
dried under cover for a longer period. The yellow color is pro- 
duced by the use of saffron or of a coal tar dye. 

Domestic Macaroni. — There is a constant increasing demand 
for macaroni made in the United States. The hardest variety 
of wheat is Used especially the hard wheat of Kansas and that 



106 FOOD INDUSTRIES 

grown in the semi-arid land. The drying, especially in the eastern 
states is done entirely indoors, the lengths being hung over 
wooden rods in heated apartments through which currents of air 
are driven. The product is very satisfactory and the sanitary 
conditions connected with the manufacture are largely in advance 
of those under which many imported brands are produced. 

Judging Quality. — A good quality of macaroni should have a 
soft yellowish color, should be rough in texture, elastic, hard, and 
should break with a smooth, glassy fracture. In boiling it should 
double its original size and should not become pasty or adhesive. 

As a Food.- — Macaroni is a very palatable and nutritious food. 
It can be kept for a length of time without deterioration and is 
comparatively inexpensive. Being high in protein it can readily 
replace meat in the diet. 



CHAPTER VIII. 



LEAVENING AGENTS. 

Early in the history of the human family, it was found that 
in order to make bread easy to masticate and more readily digest- 
ible, it must be puffed up before it was baked. This could best 
be accomplished by a gas with heat to expand it. C0 2 was the 
first gas used, obtained through the agency of yeast, and nothing 
has ever been found that can equal its action as a leavening agent. 

Advantages. — I. C0 2 is generated by the action of the yeast 
enzyme on the carbohydrate of the meal or flour, so no foreign 
substance is introduced into the dough. 

II. The slow liberation of the gas causes it to have its full 
effect as a leavening agent. 

III. The by-products produced during fermentation give a 
pleasant taste. 

IV. Bread made by yeast is more easily digested. 
Disadvantages. — I. The time required for leavening is long. 

II. Careful watching and studying of favorable conditions for 
the growth of yeast are necessary or the result will be sour or 
sodden bread. 

III. It involves a loss of carbohydrate in the formation of 
products which are volatile at the baking temperature. 

IV. As yeast is a living organism, it is impossible to calculate 
the amount of gas produced. 

Chemical Agents. — The necessity of sometimes raising bread 
quickly has led to a study of chemical agents which will produce 
C0 2 . With this method the gas is liberated in the presence of 
water by the action of an acid or acid salt on a carbonate, usually 
in the form of a bicarbonate. The salt resulting from the chem- 
ical action of the acid and base remains in the dough. 

Advantages. — -I. The time is shortened. In a few minutes a 
light, spongy dough can be prepared which would require hours 
by the use of yeast fermentation. 

II. No loss of the carbohydrate is involved. 



IOS FOOD INDUSTRIES 

III. It is possible to calculate the amount of gas which may 
be produced if the composition of the chemical reagents is known. 

Disadvantages.- — I. The taste is not as good as that of bread 
raised by yeast. 

II. The product is not as readily digestible. 

III. The residue resulting from the chemical reaction remains 
in the loaf. As these residues have no nutritive value, they can 
only be regarded as waste products. 

Early Use of Chemical Agents. — Long before the scientific inves- 
tigation along the line of these reagents was begun, the house- 
wife was making use of the same principle in the utilization of 
sour milk and saleratus to lighten dough. Although this method 
was very effective, it had two serious drawbacks: I. The acidity 
of the milk was apt to be over-estimated. Lactic acid is caused 
by the action of bacteria in milk on the lactose or milk sugar. 

C 12 H 22 O u -H 2 0- 4C 3 H 6 3 . 

When 0.9 per cent, is formed the action is stopped, the lactic 
acid acting as a preservative. In sour milk as used for cooking 
purposes, the acidity rarely exceeds 0.4-0.5 per cent. As a rule 
too large an amount of saleratus was used thus giving an excess 
of alkali. This affected the taste and interfered with protein 
digestion. 2. The saleratus of to-day is not KHCO,, but a 
cheaper and stronger compound NaHCO s , approximately four 
parts of which according to the molecular weight, will do the 
work of five parts of the potassium compound. Old recipes 
should, therefore, be reduced to j4 of the amount suggested. 

Baking Powders. — The introduction of baking powders some 
fifty to sixty years ago was a great advantage although the early 
powders were very crude. The first one prepared had for its 
ingredients Na 2 CO s and H 2 S0 4 , but this proved too troublesome 
to be practical. Liebig suggested the use of the NaHCO, and 
HC1 which would give a residue of NaCl, a perfectly harmless 
product. The bicarbonate was found to be so satisfactory that 
its use has continued to the present time, but experimentation 
soon proved that the acid could not, be used. Commercial HCl 
almost invariably contains traces of arsenic, minute quantities of 



FOOD INDUSTRIES IO9 

which could be found in the dough. Another acid was sought, 
one which could be effective, comparatively cheap, with good 
keeping qualities and which would give a harmless residue. Tar- 
taric acid was finally chosen. It was expensive and difficult to 
keep but it was effective and harmless. Bicarbonate of soda and 
tartaric acid were tried, both in the powder form. For the sake 
of convenience these powders could be mixed together. When 
dry, they did not exert any effect on each other but atmospheric 
moisture was so quickly absorbed, that chemical action took place 
and much carbon dioxide was lost. An early improvement was 
the addition of starch or some other substance having hygro- 
scopic property. Starch absorbs moisture readily and will also 
tend to keep apart the particles of the acid and base. Another 
improvement was soon made. Tartaric acid was found to be 
harmless and efficient but it was expensive and objectionable 
from a practical standpoint. On account of its great solubility, 
too rapid evolution of gas occurred. The acid potassium salt, 
cream of tartar, was less expensive, very effective and perfectly 
harmless. As it was not so soluble, less loss occurred. These 
were known as the tartrate powders. 

Tartrate Pozvders. — The first powder of commercial impor- 
tance contained three ingredients, bicarbonate of soda, cream of 
tartar and starch as a filler. Much advertising led to a rapid 
growth in the use of these powders and in a short time they 
became very popular. The method of manufacture was simple 
and the profits were enormous. Chemistry was searched for 
other combinations which could be used for leavening bread. 
Two acid salts were soon discovered which could be substituted 
for cream of tartar. 

1. Phosphate and Alum Pozvders. — Calcium acid phosphate, a 
salt of about the same strength as cream of tartar, but cheaper in 
price. 

2. Potash alum, a salt of great leavening power and very low 
in cost. 

Formulae were devised by chemists which made possible the 
use of either one or both of these salts in combination with bi- 



IIO FOOD INDUSTRIES 

carbonate of soda, starch being added as a filler. The powders 
were known as the ' phosphate, the alum phosphate and the 
straight alum powders. 

The introduction of less expensive salts and the simplicity of 
the process of manufacture led hundreds of individuals and com- 
panies into the baking powder business and great competition 
followed. Until the passing of the law prohibiting their use, 
there were many straight alum powders on the market. They 
contained starch as filler, bicarbonate of soda and potassium, 
sodium or ammonium aluminium sulphate. They were very ef- 
fective but were found so objectionable, on account of the amount 
of alum present that their sale has been practically abolished. 

The powders on the market at the present time are tartrate, 
phosphate and alum phosphate. There has been much contro- 
versy as to the relative merits of these powders, the chief point 
of discussion being the residue, "What is it?" "What amount is 
present?" "Is it harmful?" A glance at the following reactions 
and table will give some idea of the relative value. 

TARTRATE POWDER. 

188 84 54 282 44 

KHC 4 H 4 6 + NaHCO, + 3H 2 — NaKC 4 H 4 6 ,4H 2 + C0 2 

20 per cent, filler. 

1 level T. of powder weighs 3.00 grams and contains 20 per 
cent, of starch. This yields approximately 0.4 gram C0 2 or 
200 cubic centimeters at o° C, which becomes 273 cubic centi- 
meters at ioo° C. the highest temperature of the oven. The 
residue of crystallized Rochelle Salts amounts to 2.5 grams. 

PHOSPHATE POWDER. 

234 168 180 

CaH 4 (P0 4 ) 2 + 2NaHCO, + ioH 2 — 

. 136 358 88 

CaHP0 4 + Na 2 HP0 4 .i2H 2 + 2C0 2 

CaHP0 4 is insoluble in water; it requires free acid for solution. 

1 level T. of powder weighs 4.4 grams and contains 25 per 

cent, of starch. This yields approximately 0.72 gram CO., or 



FOOD INDUSTRIES 



III 



355 cubic centimeters at o° C. which becomes 485 cubic centi- 
meters at ioo° C. the highest point of the oven. The residue of 
phosphates weighs 4.05 grams. 

ALUM PHOSPHATE POWDER. 

475 234 336 

(NH 4 ) 2 A1 2 (S0 4 ) 4 + CaH 4 (P0 4 ) 2 + 4 NaHC0 3 + 
144 245 192 

8H 2 — > A1 2 (P0 4 ) 2 + CaS0 4 ,2H 2 + 

132 644 176 

(NH 4 ) 2 S0 4 + 2Na 2 S0 4 ,ioH 2 + 4C0 2 
1 level T. of powder weighs 2.85 grams and contains 33^3 per 
cent, of starch. This yields approximately 0.32 gram C0 2 or 
160 cubic centimeters at d° C. which becomes 218 cubic centi- 
meters at ioo° C. the highest point of the oven. Residue weighs 
2.17 grams. 





Weight of 
1 T. of 
powder 


Weight of 

1 T. of 

powder 

less the 

filler 


Weight 
of COo 


Volume 
of COo 
at o° C. 


Volume 
of COo at 
the oven 
tempera- 
ture 


Weight 
of the 
residue 


Remarks 


Tartrate . . 


3 grams 


2.4 grams 


0.4 gram 


200 c.c. 


273 c.c. 


2.5 grams 

All soluble 

in water. 


Residue contains 
water of crys- 
tallization. 


Phosphate 


4.4 grams 


3.3 grams 


0.72 gram 


355 c.c. 


485 c.c. 


4.05 grams 
27.55b insol- 
uble in 
water. 


Residue contains 
water of crys- 
tallization. 


Alum 
phosphate 


2.85 grams 


1. g grams 


0.32 gram 


160 c.c. 


218 c.c. 


2.17 grams 
36.6 fo insol- 
uble in 
water. 


Residue contains 
water of crys- 
tallization. 



Eelative Efficiency. — I. Alum phosphate powders are the 
cheapest, but they do not keep well. They contain alum which 
is supposed to have a deleterious effect on the system and leave 
a residue which is partly insoluble in water. 

II. Phosphate powders are cheap, but they do not keep well 
and leave a residue which to some extent is insoluble. 



112 FOOD INDUSTRIES 

III. Tartrate powders are expensive, but they keep well so 
are effective when old. They yield a residue of Rochelle Salts 
which is soluble in water. 

Tartrate powders may be prepared at home by thoroughly 
mixing ^2-pound of cream of tartar, x 4-pound of bicarbonate of 
soda and %■ -pound of starch or lactose. Lactose has been found 
to be very effective as a filler. It has great lasting power but is 
more expensive. 

Ammonia Powders. — Bakers are now using ammonia carbonate 
very effectively as a leavening agent. It has the great advantage 
of leaving no residue, but must be used in very small quantities 
or the product will taste of ammonia. 

(NH 4 ) 2 C0 3 — 2NH 3 +,C0 2 + H 2 0. 

Cream of Tartar. — Almost all of the cream of tartar and tar- 
taric acid used in this country is imported, the largest amount 
coming from Germany and France. They are by-products of 
the wine industry being obtained from a certain kind of sour 
wine. Cream of tartar or potassium bitartrate is a normal con- 
stituent of grapes, occurring in comparatively large amounts. 
When the fruit is crushed and pressed in the preparation of 
wine, most of the tartrate salts being soluble passes out with the 
juice. There is no tendency for it to become insoluble and pre- 
cipitate out in crystalline form until the grape juice reaches 5-6 
per cent, of alcoholic strength. This occurs during the fermen- 
tation process. It is customary to float branches of the grape 
vine in the fermenting vats. As the alcohol increases, gradually 
cream of tartar is deposited upon the sides of the vat and on the 
floating branches. The crystals carry down with them the color 
of the wine. They are known commercially as "argol." There are 
usually from one to three inches of a dark deposit at the bottom 
of a full barrel of new wine after it has stood long enough to 
settle, called the "lees." From argol, cream of tartar is made. 
"Lees" contains a larger amount of calcium tartrate and is used 
more extensively for the production of tartaric acid. 

Argol is not pure cream of tartar as it carries down in pre- 
cipitating, other constituents of the grape. These impurities 



FOOD INDUSTRIES 113 

must be removed. In the process of refining, the crystals of 
argol are powdered, dissolved in boiling water and filtered to 
remove dirt and other foreign matter. The color can be removed 
with egg albumin or by filtering while hot through bone-black. 
The solution is then run into shallow receivers and as the clear 
liquid cools, cream of tartar separates out and is deposited in 
thick masses of crystals. These crystals may be further purified 
by again dissolving in hot water and recrystallizing. When all 
the impurities are removed, the crystals are powdered in a mill 
and are then ready for the market. 

Tartaric Acid. — Tartaric acid may be prepared from the lees 
by the action of sulphuric acid. The calcium is removed in the 
form of a sulphate. 

CaC 4 H 4 O s + H,S0 4 -~ H. 2 C 4 H 4 O t; + CaS0 4 
Tartaric acid is used largely in pharmacy and in the textile in- 
dustry, either as the acid or as tartar emetic in certain dyeing 
processes and in calico printing. 

Acid Phosphate of Lime. — Acid phosphate of lime occurs in 
different forms. The soluble acid phosphate as used in the bak- 
ing powder industry does not occur in nature, but must be manu- 
factured. The skeletons of animal life are largely employed for 
this purpose. Here calcium phosphate Ca 3 (P0 4 ) 2 appears in 
a form insoluble in water, but which can be readily made soluble 
by treatment with an acid. 

Ca,(P0 4 ) 2 + 2 H 2 S0 4 — CaH 4 (P0 4 ) 2 + 2 CaS0 4 
insoluble soluble 

The material utilized in this industry is usually obtained from 
certain sections of the country where large deposits of phos- 
phate of lime have been found. This has been caused by sharks 
and other forms of animal life having been deposited in past 
ages, and through the process of weathering all organic matter 
has disappeared, leaving only the material which has constituted 
the frame work. This material is dug up and changed to a form 
which can be utilized in the baking powder industry. 

Bicarbonate of Soda. — The preparation of soda constitutes 
to-day one of our largest and most important industries. An 



114 FOOD INDUSTRIES 

alkali has been used for cleaning purposes by the housewife, for 
many centuries, but this represents only about one per cent, of 
the soda manufactured. It is also needed in many industries 
such as soap-making, glass manufacture and in the bleaching of 
cotton and linen goods. 

The original alkali used was potassium carbonate obtained 
from potassium salts which are widely spread throughout plant 
life. The early housewife obtained her supply from the ashes 
of her wood fire. Boiling water was poured over the dead embers 
of the fire, and the solution was boiled down giving a lye which 
could be used for cleansing purposes. For many years, the 
manufacturer was forced to depend, also, on the leaching of 
wood ashes or on natural deposits of potash which have been 
found in certain parts of the world. The largest deposits occur 
on the western coast of South America and in the region of 
North Germany which has Starsfurt as the center. 

It was not until the 18th century that another alkali was found 
to take its place. This was discovered by the Spaniards who 
prepared it by burning to ash a sea-weed found along their coast. 
It contained a sodium compound which yielded a carbonate on 
heating. The soda compound, being stronger and cheaper than 
potash, was readily received by the manufacturers and used by 
them, until the early days of the 19th century. Warfare at that 
time interfered with commerce and Spain being hostile, the 
French manufacturers were cut off from their source of supply. 
Napoleon was determined to get some means of replacing this 
alkali and as France was poor in mineral deposits, he offered a 
reward for the discovery of a practical process for making 
sodium carbonate. Everything used in the manufacture, how- 
ever, must be obtained in France. Many chemists worked at 
this problem and a process was finally discovered by Le Blanc 
which is used in many places at' the present time. 

Le Blanc Method. — Le Blanc used in the preparation of soda, 
dry salt which he obtained from the sea, by the process of evap- 
oration. He then mixed together salt and sulphuric acid. 
2 NaCl + H a S0 4 — Na 2 S0 4 -f 2HCI 



FOOD INDUSTRIES 115 

Na 2 S0 4 was known as the salt cake. It was broken up and 
mixed with powdered coal and limestone and was then treated 
in a reverberatory furnace. 

Na 2 SO, + 2C — Na 2 S + 2 CO, 
Na 2 S + CaC0 3 — * Na 2 CO„ + CaS 
Na 2 C0 3 an impure form, known as soda ash, could be dissolved 
out and the water afterwards evaporated. To obtain pure 
Na 2 CO s , the soda ash must be again heated with coal and other 
soda compounds be changed to the carbonate form. 

Bicarbonate of soda can be easily obtained from sodium car- 
bonate. 

Na 2 CO s -(- H 2 + C0 2 — 2NaHCO :s 

Hydrochloric acid was practically unknown commercially until 
the invention of the Le Blanc process of soda manufacture. 
At first it was allowed to escape into the air and being washed 
down by rain it found its way into neighboring streams. This 
soon caused the destruction of animal and plant life and was 
also a waste of a valuable by-product. Later it was discovered 
that HC1 could be run into water and sold. This opened up a 
new industry and did much toward making the Le Blanc method 
a commercial success. 

When more HC1 was produced than was needed, it was soon 
found that from it chloride of lime could be prepared, and a 
valuable disinfectant and bleaching agent was placed upon the 
market. 

Value of the Le Blanc Process. — I. The raw materials salt, 
coal, limestone and sulphuric acid are common and inexpensive. 

II. The furnace and plant can be put up at a fairly low price. 

III. The by-products are important and have done much 
toward keeping this process in existence. 

Solvay Process. — The Solvay method of preparing sodium 
carbonate was invented in i860 by a Belgian named Solvay, and 
is a serious rival of the Le Blanc process. Scattered throughout 
the world are large deposits of' salt, sometimes in the dry state 
as in the salt mines of Germany and England, at other times in 
the form of brine. Brine wells occur more extensively and as 



Il6 FOOD INDUSTRIES 

the Le Blanc method required dry salt, it was found very trouble- 
some to evaporate the water. The Solvay process can make 
use of the brine. This has been a great benefit to America for 
brine wells are abundant in Michigan, Louisiana and New York 
State. Syracuse is an important center in the American soda 
industry. Brine is also much easier to handle. It is pumped 
to the surface, saturated with ammonia, and then with carbon 
dioxide. 

NaCl + H 2 + NH 3 + C() 2 — NaHC0 3 + NH 4 C1. 

NaHC0 3 is separated out by filtration. 

If sodium carbonate is wanted the bicarbonate is heated. 
2 NaHC0 3 — Na 2 C0 3 + H 2 C0 2 . 

The ammonium chloride obtained in this process can be de- 
composed by heating with quicklime, and the ammonia given off 
is again used for the treatment of another batch of brine. 

This process is cheaper than the Le Blanc and furnishes a 
purer product. 

Niagara Process.— By the use of electricity, a method of pre- 
paring soda has been discovered, which is a serious rival to 
both the Le Blanc and Solvay processes. Brine is here run 
into partitioned tanks containing electrodes. When the current 
is turned on ionization of the salt occurs. 

NaCl + H 2 — NaOH + HC1. 
NaOH passes to the negative pole in one partition as it carries 
a positive change and HC1 goes to the positive pole in the other 
partition. 

Caustic soda can readily be utilized in the preparation of the 
carbonate and the bicarbonate. 

2 NaOH + C0 2 — Na 2 C0 3 + H 2 0, 
Na 2 CO s + H 2 -f C0 2 — 2 NaHCO. s 
In this industry HC1 can again be used as a by-product for the 
preparation of chloride of lime or can be utilized in the acid 
form. 



CHAPTER IX. 



STAECH AND ALLIED INDUSTRIES. 

Starch is one of the most widely diffused substances in the 
vegetable kingdom. With the exception of the fungi, it has been 
found in varying amounts in every plant that scientists have so 
far examined. It occurs in relatively large amounts in different 
parts of the plant as in the seed (cereals), the root (cassava), 
the tuber (potato), the fruit (banana), the stem (celery, rhu- 
barb, sago), and in the leaves (spinach). 

Composition and Formation. — See Chapter I, Food Principles. 

Physical Characteristics. — To the naked eye, starch has the 
appearance of a glistening white powder. It is neutral to litmus, 
has no odor or taste, does not crystallize and has a harsh feeling 
when rubbed between the fingers. When seen through a micro- 
scope, it consists of granules of various forms, round, oval, etc., 
differing greatly in size, according to the source. This has served 
as a valuable means of identifying starch. Although the size 
and shape may differ, all starch granules have a characteristic 
appearance. They are arranged in layers around a central nu- 
cleus. The outside consists of a substance closely resembling 
cellulose and within the granule or package is found the true 
starch. 

Physical and Chemical Properties. — I. Insoluble in cold water. 

II. With iodine, starch gives a characteristic blue color. 

III. Starch absorbs moisture from the atmosphere until it 
contains approximately 18 per cent. In very damp weather, it 
has been found to absorb a much larger quantity. 

IV. When heated dry to 200 ° C. or more it is converted into 
dextrin. 

V. When heated in the presence of water, the contents of the 
granules swell enormously owing to a large absorption of water, 
and cause the rupture of the outer wall. The starch freed from 
the package, forms a viscous liquid known as starch paste. 

Uses. — While its place in the diet would alone make starch an 



Il8 FOOD INDUSTRIES 

important article of commerce, the manufacturer finds many 
another market for his" product. It is used : - 

In laundries. 

For food such as puddings, sauces and jellies. 

For candies such as gum drops and lozenges. 

In baking powders. 

In the textile industry for stiffening and finishing fabrics. 

In wall paper manufacture as a filler, finisher and size. 

For cosmetics, asbestos, soaps and adhesives. 

In brewing beer, ales and in the manufacture of alcohol. 

For the manufacture of dextrin and glucose. 

Source of Supply.— While starch is so widely distributed in the 
vegetable kingdom, there are comparatively few plants that can 
be utilized as a source of supply for the manufacture. In look- 
ing for his raw material, the starch producer must consider sev- 
eral important points: ist, the ease with which the plant can be 
grown in his locality; 2nd, the amount of starch yielded by the 
plant; 3rd, the ease of extraction; 4th, the presence of other 
constituents such as protein and oil, which makes the process 
difficult. 

With these points in mind, the European manufacturer 
chooses the potato, wheat and rice. The American uses corn 
and to a limited extent the potato and wheat. In the East and 
West Indies the cassava furnishes the chief source of starch. 
The arrowroot is utilized in the West Indies and parts of South 
America, and the sago in the East Indies. 

POTATO STARCH. 

The potato is a valuable source of starch on account of the 
great ease of extraction. The starch content is comparatively 
low as compared with corn and wheat, but protein, mineral mat- 
ter and oil are present in such small amounts that they do not 
interfere with manufacturing processes. As a rule only about 
20 per cent, of starch is found in the potato, although in certain 
parts of Germany the starch content has reached from 25-29 
per cent. 

Potatoes can be grown very easily in temperate climates such 



FOOD INDUSTRIES IIO, 

as Germany, England, Scotland and Ireland. In the United 
States, Maine is noted for the production of a high quality po- 
tato and Wisconsin and Colorado grow the potato largely for 
the starch industry. The following demonstration may be used 
to illustrate the simplicity of the method used: 

Extraction of Starch. — Clean and remove the skin from a small 
potato. Rub it on an ordinary grater, collect the gratings in a 
beaker of cold water, strain and allow the cloudy liquid to stand 
until the starch settles. Pour off the liquid. The starch can be 
purified by the addition of water, thoroughly mixing and allow- 
ing the starch to again settle. Remove the water by filtration 
and dry the starch with low heat. 

Although the manufacturer uses more or less complicated 
machinery to carry out these operations, the commercial pro- 
cesses are practically the same. 

Processes in Manufacture. — I. Cleaning. — The washing of po- 
tatoes must be thorough or the quality of the starch will suffer. 
The adhering dirt and sand are carefully removed by washing 
in. revolving wooden drums, so constructed that the water carry- 
ing dirt and other impurities can escape through narrow open- 
ings. Inside the drums, devices such as bristle or wire brushes, 
or revolving arms which rub the potatoes together, are some- 
times used to assist in the cleansing. 

II. Rasping. — The potatoes are reduced to a pulp in machines 
called raspers. These are usually revolving cylinders containing 
saw blades or knife edges to assist in the pulping process. Water 
is added at the time of rasping and the starch pulp is fed to a 
sifting machine. 

ill. Sifting. — Shaking tables covered with gauze separate the 
starch grains from the potato pulp. The pulp can be pressed 
and dried. It is sold as a low grade cattle food. The starch 
suspended in water passes through the sieves to settling tanks. 
When it 'has settled in a firm mass, it can be broken up and sent 
at once to a drying kiln or can be further refined. 



120 



FOOD INDUSTRIES 



All root starches follow the same principle in the extraction 
of the starch. 

TAPIOCA. 

Tapioca is an important food product prepared from the 
starch of the cassava, a plant grown largely in Brazil and other 
tropical countries. The extraction of the starch is carried out 
by the processes of grinding and washing with water, similar to 
those described under potato starch. The product is sometimes 
known as Brazilian arrowroot. In the manufacture of tapioca, 
the starch while still damp is placed in shallow pans and sub- 
jected to low heat. As the moisture is driven off, the tempera- 



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Mill Publishing Co.) 

ture is gradually raised until the starch granules burst and ad- 
here together, forming the mass into small irregularly shaped 
translucent kernels. A similar product may be obtained by mak- 
ing a starch paste, subjecting it to heat, and forcing it through 
metal screens from which it is dropped and cooled. Tapioca is 
placed on the market in various forms according to the amount 
of heat used and differences in mechanical operations. ) 



FOOD INDUSTRIES 121 

Starch derived from other sources may be subjected to the 
same treatment and an equally nutritious product be obtained. 
As genuine tapioca, however, is always prepared from cassava 
starch, other imitative forms must be classed as substitution 
products. 

Outline of the Corn Products Industry. — 
I. Cleaned. 
II. Kernel softened by steeping. 

III. Crushed. 

IV. Separated by gravity. 

(i) Germ flows off from the top with the raw starch 
liquor, screened from the latter, dried, ground, 
pressed. 

(2) Hulls flow off from the bottom with the raw 

starch liquor, screened from the latter, then 
ground in burr mills and become part of gluten 
feed. 

(3) Endosperm (raw starch liquor) separated by grav- 

( Starch, 
ity on tables into •< 

( Gluten, which with corn sol- 
ubles obtained from steep- 
ing water, becomes part 
of the gluten feed. 

Starch is purified and sold as 

I. Starch — laundry lump, crystal, pearl powder etc. 
1. By process of roasting. 



II. Dextrin 



2. By use of a dilute acid. 

Boiled with dilute 



III. Glucose by process of hydrolysis { 



acid 0.06 of 1% 
Neutralized. 
Filtered^. 
Decolorized. 
I. Concentrated, 



122 



FOOD INDUSTRIES 



CORN PRODUCTS INDUSTRY. 

The abundance of the growth of corn in the United States 
and the many by-products obtained, make it an important source 
of starch, although the composition of the kernel involves elabo- 
rate methods for the extraction. 

The kernel of corn consists of an outer coating called the hull, 
the germ which contains a comparatively large amount of oil, 
and the endosperm, where are found starch and protein. 

When received at the factory, the corn contains some impuri- 
ties and the kernel is in a dry, hard condition. 




Fig. 26. — Steeped Corn Running to Crushers. (Courtesy of Corn Products Refiniug Co.) 

Processes in Manufacture. — I. Cleaning. — Corn like other 
cereals contains a certain amount of foreign matter such as bits 
of corn cob, pieces of wood, lint, dust and dirt. These are re- 
moved by screening, while magnets are used for drawing out bits 
of iron, nails and the like. 

II. Steeping.— In order to separate the kernel into its com- 



FOOD INDUSTRIES 



123 



ponent parts, the hard, dry grain must first be softened. This is 
accomplished by steeping it in water for approximately 40 hours 
at a temperature of no° F. Steam is injected to maintain the' 
circulation and to keep the temperature at the desired degree 
A very small amount of acid, 6.005 P er cent. H 2 S0 3 , is added to 
prevent fermentation. This is afterwards removed by thorough 
washing. When the grain has absorbed sufficient moisture to 
cause a loosening and softening of the various parts, the water 
is drawn off, leaving the kernel of corn in a moist, soft condition. 




Fig. 27.— Crushers. (Courtesy of Corn Products Refining Co.) 

The steepwater is evaporated and the solubles of the corn are 
incorporated with the gluten feed. The steeped corn is run to 
the crushers (Fig. 26). 

III. Crushing. — The softened grain is passed through a mill 
called the crusher (Fig. 27). It consists of two large disks set 
face to face having projecting teeth and rotating in opposite di- 
rections. It is supposed to grind only to a coarse meal, thus 
leaving the germ and hull intact. 



124 



FOOD INDUSTRIES 



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Fig. 28. — Separators. (Courtesy of Corn Products Refining Co.) 




Fig. 29. — Hydraulic Presses for Oil. (Courtesy of Corn Products Refining Co. 



FOOD INDUSTRIES 1 25 

IV. Separation. — The resulting mass is fed to a long, narrow 
tank about 25 feet long, 4 feet wide and 8 feet deep, where tak- 
ing advantage of the difference in the specific gravity, a separa- 
tion of the various parts is effected. The germ being the light- 
est rises to the top and floats over the weir at the end of the tank ; 
the hulls sink to the bottom and flow off with the starch liquor 
(Fig. 28). The germs are passed over screens or shakers. They 
are then washed to free them from adhering starch, dried, 
ground fine, heated, wrapped in cloth and pressed (Fig. 29). The 
pressure causes the oil to flow out, leaving the oil cake which is 
sold for cattle food. The oil is cleared of foots by settling and 
passing through a filter press. It may be used for the manufac- 
ture of soap, soap powders, oil cloth, leather, paints and var- 
nishes. By further refining with a treatment which removes the 
free fatty acids and other impurities, corn oil can be used for 
edible purposes as a salad oil, for frying and cooking and as a 
shortening for bread and cake. In this form, it is also utilized 
for pharmaceutical purposes. By a vulcanizing process, corn oil 
yields a substance called "paragol," which can be used as a 
rubber substitute in the preparation of such articles as shoes, 
rubber specialties and automobile tires. 

V. The Hulls and the Endosperm. — The hulls flow off from 
the bottom of the separator together with the starch liquor (en- 
dosperm) just as did the germs from the top of the separator. 
They then pass over screens, the starch liquor uniting with the 
starch liquor of the germs. The hulls being coarse are ground 
in burr mills, passed over screens, the starch liquor unites with 
the starch liquor of the germs and of the hulls, and the ground 
hull becomes part of the gluten feed, being mixed with the glu- 
ten and corn solubles. 

The starch liquor (endosperm) contains the starch and pro- 
tein matter, which is spoken of as gluten by the manufacturer. 
These must next be separated. This is effected by running the 
starch liquor from the germs, hulls and ground hulls, directly 
upon tables from 60-120 feet long, 3 feet wide with a decline of 
about 4 inches. As there is a difference in specific gravity, the 



126 



FOOD INDUSTRIES 



starch settles while the liquid containing the protein flows over 
the end of the run and is caught in a tank below. The crude 
corn protein is mixed with the hulls, filter pressed, mixed with 
the corn solubles, dried, ground and constitutes gluten feed. 
The starch which settles to the bottom of the run is removed 
by being shoveled while in a solid, moist condition. The purifi- 
cation can be effected by the addition of water and again pass- 
ing over the runs on which the starch settles. This process can 
be repeated, until all foreign matter such as traces of fat and 




Fig. 30. — Dripping Boxes. (Courtesy of Corn Products Refining Co.) 



protein, are removed. Pearl starch, that to be used for baking 
powder and for certain classes of food starch, is prepared by 
breaking up the starch from the table and placing it on trays 
which are put into iron wagons, run into kilns, and dried. The 
lump starch and crystal forms are prepared by mixing the starch 
from the tables with water, then running it into boxes with per- 
forated bottom lined with cloth (Fig. 30). The boxes are allowed 
to stand until the water runs off, then turned over and the thick 



FOOD INDUSTRIES 



127 



slab of starch is broken up into cubes (Fig. 31 ). These are either 
wrapped in paper or put in trays and placed in drying ovens, 
where after ten or more days they are drawn out. 




Fig. 31. — Emptying Starch from Drip Boxes. Breaking into Cubes. 
(Courtesy of Corn Products Refining Co.) 

DEXTRINS. 

Dextrins are produced in the same factory usually by the 
simple process of roasting. The different varieties depend upon 
the time and heat applied. 

Uses for Dextrins.— For the manufacture of gums, glues, muci- 
lage and other adhesives. 

For cloth, carpets and twine. 

For leather dressings, paper and ink. 

For food sauces. 

In the textile industry, in sizes for strengthening the fiber and 
finishing the fabric. Also for thickening colors for calico and 
other printing. 



128 FOOD INDUSTRIES 

CORN SYRUP OR GLUCOSE. 

On account of its source commercial glucose is known in the 
United States as corn syrup. The term glucose is derived from 
the Greek word "Glykos" meaning sweet. It is a carbohydrate 
of the monosaccharid group, C 6 H 12 6 , and is found in nature in 
the juice of many plants such as grapes, cherries and sweet corn. 
Although it exists at times in relatively large amounts, the com- 
mercial source of glucose is always starch on account of the 
cheapness of that material, and the comparatively simple process 
of manufacture. In Europe glucose was first prepared from the 
potato starch during the early part of the 19th century, and has 
long been looked upon as a nutritious food. It was not until 
after the Civil War, however, that American manufacturers 
started experimenting with corn starch as a source of supply 
for glucose. As grape sugar and corn syrup, it was soon placed 
upon the market. The products from corn compared very fav- 
orably with those made abroad from potato starch and so rapidly 
has the manufacture grown, that it is now one of our most im- 
portant industries. 

Glucose is sold in the liquid form, either white or colored, 
with or without flavoring, and as a solid in the powdered and 
crystalline form, all under various trade names. 

Uses for G-lucose. — For confectionery, syrups, jams, jellies, pie 
filling, puddings, preserves and mince meat. 

In the brewing of beer. 

In chewing tobacco. 

In silvering glasses for mirrors. 

In liquid soaps, hair tonics, blacking and shoe polishes. 

In food sauces and in the canning of meats. 

For pastes and sizes. 

In the tanning of leather and in rice polishing. 

Processes of Manufacture — Whether in Europe or America, 
whether from potato or corn starch, the manufacturer must use 
the process of hydrolysis to obtain glucose. This is accom- 
plished by heating starch in a closed digestor, with a minute 
quantity of muriatic acid. The amount of acid used represents 



FOOD INDUSTRIES 1 29 

proportionately about a fifth of the same acid contained in the 
gastric juice. 

The heating is continued until the starch reaction with iodine 
has disappeared. At the present time, a pressure of 35 pounds 
is maintained and the operation at that pressure is finished in 
about five to ten minutes. 

On the continent and in England H 2 S0 4 is the agent used for 
hydrolysis. This is afterwards neutralized with marble dust 
which with the acid forms an insoluble precipitate. During the 
process of refining this precipitate is removed. 

H 2 S0 4 + CaC0 3 — CaS0 4 + H 2 + C0 2 . 

The American manufacturer prefers the use of HC1, although 
it is more expensive. With soda ash as a neutralizing agent, 
common salt is obtained as a residue, and being perfectly harm- 
less, the manufacturer is saved the trouble of removing it. 
American glucose, therefore, always contains sodium chloride. 
2 HC1 + Na 2 CO a — 2 NaCl + H 2 + C0 2 . 

After hydrolysis, the glucose solution is filtered to remove 
small amounts of fat and protein occurring in the starch, and is 
then decolorized by passing through bone-black, a similar pro- 
cess to that used in the cane sugar industry. It is then evap- 
orated to various degrees of concentration. 

If hydrolysis has been continued until the dry substance in 
the liquid consists of at least 86 parts of glucose, the product 
after concentration instead of being a syrup, crystallizes and 
hardens into a sugar after it has been run into barrels or pans. 



CHAPTER X. 



THE SUGAR INDUSTRY. 

Source. — The disaccharid C 12 H 22 O ia , known as sucrose or sac- 
charose, is found in a large variety of plants. It is so apt, however, 
to be accompanied by a characteristic taste of the plant, or other 
carbohydrates such as starch, glucose or invert sugar, that unless 
it appears in relatively large proportions and can successfully 
be freed from the taste, it does not pay commercially to extract 
it. For the supply of raw sugar the world is largely dependent 
to-day, on the sugar cane and the sugar beet. Sugar-producing 
plants of lesser importance in commerce are the maple tree, the 
date palm, the sorghum and the maize. 
\/ History of the Sugar Cane. — The sugar cane is by far the earliest 
plant from which sugar was extracted. Prior to its discovery, 
many centuries before the Christian era, mankind was largely 
dependent Upon honey as a sweetening agent, and the European 
nations knew little of its use until the 13th and 14th centuries. 
The original home of the cane was undoubtedly in the east, for 
mention of it is made in many of the sacred books of the Hin- 
doos and Chinese. Its cultivation was gradually carried west- 
ward, by the Persians and Arabs, and at the time of the cru- 
sades, sugar factories were found in operation in Syria and Pales- 
tine. Carried still further westward by the Saracens and Moors, 
it was finally introduced into Sicily and Spain. The discovery 
of America shortly after this period led the Spaniards to carry 
the plant to the New World, where it was found that it could 
be successfully grown on the mainland and on adjacent islands. 
This opened a new field for the growth of the cane and laid the 
foundation of a great industry. 

History of the Sugar Beet. — The history of the sugar beet in- 
dustry dates only as far back as the early days of the 19th cen- 
tury. A half century before its introduction, the German chemist 
Margraff had called the attention of the Berlin Academy of 
Science to the fact, that sugar could be extracted from the beet. 
This discovery, however, lay dormant until an important histori- 



FOOD INDUSTRIES I3I 

cal event cut off the European nations from their supply of cane 
sugar. South-western Europe, at that time, was involved in 
warfare and a great continental blockade was established by the 
English fleet. The nations of Europe deprived of cane sugar 
searched for another supply to take its place. Sugar from the 
maple and glucose from the juice of grapes, were used but could 
not supply the demand. A former pupil of MargrafF, Achard, 
finally turned the attention of scientists to the beet, and a long 
series of investigations followed which had for its final outcome 
the birth of the beet sugar industry. It was first established in 
France by a decree issued by Napoleon, January 15th, 181 1 and 
was greatly fostered by him until the disastrous Russian cam- 
paign. Although the fall of that dynasty interrupted, it did not 
destroy the industry, and in the course of twenty years it had 
become of great commercial importance. Undoubtedly, the great 
progress in this industry was largely due to the invention of the 
polariscope, which greatly assisted in a rapid determination of 
the amount of sugar present in the beet. 

About this period German scientists became interested, and 
through their experimentation, marked progress was made in the 
cultivation of the beet and in the methods of manufacture, which 
in time placed Germany at the head of the sugar producing coun- 
tries of the world. While the beet sugar industry has reached 
its highest development in Germany, it is rapidly becoming an 
important source of sugar in the United States. 

Comparison of Cane and Beet Sugar. — Since the time that beet 
sugar began to assume commercial importance, there has been 
much discussion in regard to the relative merits of these sugars, 
for use in the household. Scientists claim that chemically they are 
the same, both having the formula C 12 H 22 11 , yet it has often 
been said that beet sugar is not as sweet as cane sugar, and that 
it cannot be used successfully for canning, jelly-making and pre- 
serving. Experiments along this line were carried on at the Cali- 
fornia Experiment Station by Prof. G. W. Shaw. The con- 
clusion drawn from his experimental data was that sugar derived 
from these two sources give equally satisfactory results, both in 



132 FOOD INDUSTRIES 

the household and for commercial purposes. Any differences 
occurring seemed due rather to processes of manufacture such as 
degree of fineness in granulation, rather than to the composition 
of the sugars. 

Properties of Sugar. — From the manufacturer's standpoint, 
there are three important properties to be considered in preparing 
the raw material for the market ; 1 st, solubility in water ; 2nd, 
crystallization; 3rd, production of invert sugar. 

THE CANE SUGAR INDUSTRY. 

The manufacture of cane sugar as a rule is divided into two 
distinct industries: 1st, the plantation where the plant is grown, 
the juice extracted and made into raw sugar, the form in which 
it is exported; 2nd, the refinery where the raw sugar is received, 
impurities removed and the sugar recrystallized, in which form 
it is placed upon the market. 

At the Plantation. — Growth. — The sugar cane belongs to the 
family of grasses. It can be grown in a variety of climates, but 
thrives best where it is moist and warm with intervals of hot, dry 
weather. Such conditions are found near the coast in tropical 
and sub-tropical countries. Cuba, Hawaii, Porto Rico, the Philip- 
pine Islands, all raise the sugar cane extensively. In the United 
States this industry is confined to the Gulf States especially 
Texas and Louisiana. 

Outline; of the Production of Raw Sugar. — 
I. Cane cut in the green stage. 

II. Cane crushed { ^e^uice. 

III. Crude juice screened -] . . y 

J (juice. 

IV. Juice treated with milk of lime; residue removed. 
V. Juice concentrated. 

a. Boiled down in open kettles. 

( TTlolclSSCS 

Drained in hogsheads or casks j muscovado sugar 

b. Boiled down in vacuum. 

Separated in centrifuge j molasses - 
( raw sugar. 



FOOD INDUSTRIES 



133 



Cutting. — The sugar cane, when the crop is ready, is harvested 
by cutting the stalks as close to the ground as possible. Consid- 
erable care must be given that the plant be cut at the right time, 
for should it reach maturity, much sugar would be lost to the 
manufacturer. The sugar cane contains a substance known as 
pectose which in time changes to pectic acid. The presence of 
this acid rapidly converts the sugar into invert sugar which is 
not crystallizable. The sugar planter knowing well the damage 
this acid will do to his product, cuts the cane while it is still green. 




Fig. 32. — Cane Mill, Philippines. 
(Courtesy of the School of Mines Quarterly, Columbia University.) 

At the "green stage," the plant contains the maximum amount 
of sugar and the minimum of undesirable substances. After 
stripping the leaves from the stalk and removing the green upper 
portion, the cane is taken to the mill for the extraction of the 
juice. 

Extraction of the Juice. — The most common method used with 
the cane is the crushing process by means of heavy mills. The 
cane-mills of to-day are of various types ranging from the crude 
ox-driven mill of primitive countries (Fig. 32) to a high power 
steam-driven roller mill where the most modern machinery can 
be found. As the cane is received at the mill, it is delivered by 



i34 



FOOD INDUSTRIES 



carriers to high crushers (Fig. 33), which reduce the stalks to a 
pulpy fiber and extract much of the juice. This mass then passes 
to a mill composed of three rollers of the same size, set in such 
a way that the first and second are not so close together as the 
second and third. The rollers draw the cane within their grip, 
subjecting it on its passage to great pressure, and causing the 
rupture of the cells and the escape of more of the juice. A second 
and third mill are sometimes used, more and more of the juice 
being extracted by each roll. It is customary to spray the pulp 



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Y '- 


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Fig. 33. — Cane Crusher, Hawaii. 
(Courtesy of the School of Mines Quarterly, Columbia University.) 



as it passes between the rolls to secure a greater degree of ex- 
traction. From the roller-mill two products are obtained, the 
exhausted cane which is called begasse, and the extracted juice 
which must be purified before it can be converted into raw 
sugar. 

Even with modern machinery, the extraction of juice by this 
method is by no means perfect, — only from 75 to 80 per cent, of 
the weight of cane in juice is obtained. As the sugar cane con- 
tains approximately 88 per cent, a considerable portion of the 
sugar is lost in the begasse. Much experimenting has been done 



FOOD INDUSTRIES 



135 



to remove the juice from the cane by a method which will involve 
less loss. The diffusion method used so largely in the beet sugar 
industry has been tried, but at present is being used in but few 
of the large plantations in the United States. 

Purification of the Raw Juice.— The second important step is 
the purification of the raw juice by straining, to remove bits of 
cane, and the addition of a clarifying agent. Milk of lime is the 
agent most commonly used and the mass is heated to boiling. 
This prevents fermentation, neutralizes the free organic acids 




Fig. 34. — Open Pan Evaporators, Philippines. 
(Courtesy of the School of Mines Quarterly, Columbia University.) 



of the juice and assists in the coagulation of the dissolved matter 
A thick scum of impurities rises to the top of the kettle. This 
consists of lime salts and albuminous matter and is known as 
"the blanket scum." The impurities are removed by skimming 
and by sedimentation and passage through a filter press. 

Evaporation. — The concentration of the juice may be carried 
out in two ways: 1st, the old-fashioned method of boiling down 
in an open kettle; 2nd, by the use of the vacuum pan. Large 
open pans or kettles usually made of copper and heated over 
direct fire are found now, only in primitive countries or on iso- 
10 



136 



FOOD INDUSTRIES 



lated plantations (Fig.. 34). Their use has been found to involve 
a great loss of sugar, although the product obtained had an 
agreeable aromatic taste much preferable to the refined sugar of 
to-day. It was customary to boil down the sugar juice until the 
mass began to crystallize. This necessitated a rise in temperature 
from 212 to 240°-25o° F. and resulted in the formation of 
caramel and invert sugar which must be looked upon as waste, 
from the standpoint of the manufacturer. After crystallization 
had reached the desired point, the mass was freed from the syrup 
by simply being run, while hot, into hogsheads having line perfor- 
ated bottoms, through which the molasses gradually drained out. 




Fig- 35- — Vacuum Pans, Hawaii. 
(Courtesy of the School of Mines Quarterly, Columbia University. 



The light brown sugar obtained as a result of this process was 
known as "muscovado" sugar. The molasses was very dark in 
color but of excellent quality and without further treatment 
could be used as a table syrup. 

In all modern sugar mills, evaporation is carried on in vacuum 
pans where concentration can be brought about with a lower 
temperature, i6o°-i8o° F., thus avoiding the losses always oc- 
curring in the open kettle method. The vacuum pan invented 
in England in 181 3 is a large closed vessel usually made of cop- 
per containing steam-coils for heating, the vacuum being, main- 



FOOD INDUSTRIES 



137 



tained by a pump (Fig. 35). Suitable openings are made in the 
side for the entrance and exit of the juice, a window is inserted 
where the operation can be watched, and an opening from which 
samples can be taken and tested. When the vacuum pan was 
first' introduced into this industry only one was used. It has 
been found of great economic value, however, to use the vacuum 
evaporators in series of two, three or more, known as the mul- 
tiple effect vacuum (Fig. 36). When arranged in series, a low 




Fig. 36.— Multiple-effect Evaporating Apparatus. 

vacuum is maintained in the first vessel, a little higher in the 
second and still higher in the third and so on. The boiling point 
for each succeeding vessel is thus reduced. When the system is 
in operation, the steam arising from the juice in the first vessel 
passes to the coils of the second vessel and serves as a heating 
agent. The steam from the juice of the second vessel in turn 
serves as a heating medium for the third vessel. After the 
clarified juice has been evaporated to a syrup, it is run into a 
single vacuum pan known as "the strike pan" when a high degree 



133 



FOOD INDUSTRIES 



of vacuum is maintained (Fig. 37). There it is concentrated 
until the sugar begins to grain. Crystallization is allowed to 
continue until the pan is full of crystals the desired size. The 




Fig' 37- — Vacuum Strike Pan. 



mixture of crystals and syrup is known as "massecuite." The 
vacuum is then broken, air is admitted and the bottom of the 
pan is opened so the contents can be transferred to a mixing ap- 
paratus where the massecuite is kept in gentle motion. While 



FOOD INDUSTRIES 



139 



still warm, the mixture is passed to a centrifugal machine which 
causes a separation of the crystallized sugar and the molasses. 

Centrifugal. — The centrifugal or centrifuge is a hollow iron 
drum containing a perforated basket (Fig. 38). It can be rapidly 
rotated during which the sugar mass is thrown against the sides 
of the basket and the molasses passes through the perforations. 
The sugar is then bagged and shipped to the country where it is 
to be refined. 




Fig. 38. — Centrifugal Machines. (Courtesy of Sugar, Chicago, 111.) 

This is known as "the first sugar" and the molasses drained 
from the sugar is called "the first molasses." This molasses may 
be sold for household use or as it contains much sugar, it may 
be again worked over. This is accomplished by boiling it down 
in vacuum and again centrifuging. By this means a second 
sugar and a second molasses are obtained. The second molasses 
may again be boiled down for a third sugar and molasses. While 



140 



FOOD INDUSTRIES 



the third molasses still contains about 30 per cent, sugar, it con- 
tains so many impurities that the sugar will not crystallize out. 
THE BEET SUGAR INDUSTRY. 
Growth. — Unlike the cane, the sugar beet reaches its highest 




Fig. 39. — The Wild Beet. (Courtesy of Sugar, Chicago, 111.) 

development in a north temperate climate, although where the 
soil has exceptionally good qualities, it has been grown success- 



FOOD INDUSTRIES 



141 



fully in sub-tropical regions. It is not apt, however, to contain 
as much sugar. Moisture also plays an important part in the 




Fig. 40. — The Sugar Beet of To-day. (Courtesy of Sugar, Chicago, 111.) 

production of a normal crop. The sandy soil, temperature, and 
moisture near our western rivers in Colorado, and neighboring 
States, furnish satisfactory farm land for this industry. Beets 



142 



FOOD INDUSTRIES 




FOOD INDUSTRIES I43 

can also be grown successfully in irrigated areas and much waste 
land, it is hoped, may be utilized in this way. Much experiment- 
ing is being done in regard to the cultivation of the beet, -and 
great improvement has been made especially in increasing the 
sugar content (Figs. 39 and 40). The average percentage of the 
sugar is 13-14 per cent., while on the irrigated area it has been 
increased to 16-18 per cent. The yield per acre is still low, 
however, not exceeding eight tons, while in Europe twelve to 
thirteen tons are obtained (Fig. 41). 

Outline; of the: Production of Raw Sugar. — 
I. Beets are grown, harvested, topped. 
II. Washed. 

III. Sliced. 

IV. Diffused { P ul g- • • 

( crude juice. 

V. Crude juice is screened. 
VI. Defecated. 

VII Filtered { albuminous matter, etc. 
( juice. 

VIII. Concentrated in vacuum. 

IX. Centrifugedj mola K SSe f- 

& ( raw beet sugar. 

Topped. — After harvesting, it is necessary to remove the tops 
with a small part of the neck of the beet. The object of remov- 
ing this portion is to prevent the large accumulation of mineral 
matter at the top from entering the factory, as it interferes with 
the crystallization of the sugar. This work is done in Europe 
as a rule by women and children. In the United States, foreign 
labor is gradually replacing the custom of sending whole families 
into the field during the harvesting season. 

Washing. — On entering the factory, the beets are first washed 
to remove adhering soil, sand and pebbles. This work is accom- 
plished in long troughs, each containing a revolving shaft which 
carries pins set in the form of a screw. These push the beets 
along the trough against a stream of water, and the rubbing 
against one another loosens the dirt, which is carried away by 
the water. 



144 



FOOD INDUSTRIES 



Extraction of the Juice. — In considering the method of extrac- 
tion of the juice from' the beet, the composition plays an impor- 
tant part. In the beginning of this industry, the crushing process 
was used similar to that employed with the sugar cane, but was 
found so unsatisfactory that it has been almost entirely replaced 
by the diffusion process. 



Water 

Fiber, etc 

Sucrose 

Invert sugar 

Mineral matter 
Nitrogenous matter 
Germs, acids, etc • . 
Wax, fat, etc 



Composition of the 


Composition of the 


sugar cane 


sugar beet 


67-75% 


75-85 


IO-15 


4-6 


II-16 


I2-l6 


Q-5-I-5 


0.0-0.3 


0.5-1.0 


0.S-I.5 


0.4-0.6 


1 -5-2-5 


0.2-0.5 


0.4-0.8 


0.4 


0.2 



A comparison of these two important sugar yielding materials 
will reveal marked differences in composition, which make neces- 
sary the employment of different processes, for the extraction of 
the sugar. The cane which contains a relatively large proportion 
of fibrous material yields very readily to crushing by rollers, 
while the beet containing more water and less fiber is reduced 
to a pulpy mass very difficult to handle. It may also be noted 
that the beet contains more nitrogenous and mineral matter and 
less invert sugar than the cane. 

Slicing. — In order to obtain the best results with the diffusion 
method, the beets are sliced into thin pieces by a machine con- 
taining revolving knives. These slices are known as chips in 
English, corsettes in French and schnitzel in German. 

The chips after being weighed are run into vessels in which a 
current of warm water displaces the juice in the beet by the 
process of osmosis. Foreign matter which is colloidal cannot 
pass through the cell walls of the beet; the sugar being crystal- 
line, however, passes out into the water. 

The Diffusion Battery. — The vessels in which the sugar is 
extracted are known as diffusion batteries (Fig. 42). They 
are usually arranged in a series of 10-12 upright iron cylinders 



FOOD INDUSTRIES 



145 



called cells which are connected by pipes, the outlet from the top 
of one cell passing downward into the bottom of the next, and 
so on through the entire series. The cells can be placed in a 
row or in a circular position. 

When ready for operation, the chips are fed by means of a 
swinging trough into the cells through a manhole at the top, and 
warm water about 140 F\ is passed through the system. The 




Fig. 42.— The Circular Diffusion Battery. (Courtesy of Sugar, Chicago, 111.) 



circulating liquid remains about twenty minutes in each cell, 
removes sugar from the beet chips and is passed to the next cell. 
Heaters or "juice warmers" are placed between the cells to again 
raise the liquid to the desired temperature. As the juice passes 
from battery to battery, it grows stronger in sugar content. When 
it has become sufficiently concentrated it is sent to the defecating 
room and fresh water is passed through the batteries. The 
process is continued until practically all the sugar has been re- 



I46 FOOD INDUSTRIES 

moved from the beet chips. There is rarely more than 0.5 per 
cent, loss of sugar with this method of extraction. 

During the sugar season, the battery is constantly in use. Being 
arranged in series, it is possible to circulate liquid through from 
8 to 10 cells while two are being emptied and refilled with fresh 
chips. 

Clarification of the Juice. — The sugar solution known as "the 
diffusion juice" is almost as black as ink as it comes from the 
batteries, and must, therefore, be clarified. This is usually accom- 
plished by adding an excess of lime, heating, and treating with 
C0 2 . The lime is converted into the carbonate form and in pre- 
cipitating carries down much of the impurities which are re- 
moved by a filter press. The process is usually repeated two or 
three times or until the liquid is clear. The first carbonation is 
stopped when the greater part of the lime has been precipitated, 
but while there is still about 0.1 per cent, of lime in solution. 
The impurities precipitated with the carbonate of lime are insol- 
uble in an alkaline solution, but redissolve in a neutral solution. 
After the first carbonation, the juice is filter-pressed to remove 
the precipitated carbonate of lime and impurities, and then car- 
bonated a second time to precipitate most of the remaining lime, 
this time to an alkalinity of 0.02 or 0.03 per cent. The second 
filtration is usually through gravity filters where only a very 
gentle pressure is applied. 

The clear juice is then concentrated in vacuum and separated 
by the centrifuge into molasses and raw beet sugar, the processes 
being similar to those used for cane sugar. 

Raw beet sugar contains substances of decidedly unpleasant 
odor and taste, due to nitrogenous matter and mineral salts being 
taken up from the soil by the roots of the beet. It must, there- 
fore, always be refined even when modern machinery and up-to- 
date methods have been used. The molasses obtained can be 
worked over until most of the sucrose has been obtained. It is 
very impure, however, from mineral salts and nitrogenous com- 
pounds, which give it so disagreeable an odor and taste that it 
is never fit for table use. 



FOOD INDUSTRIES 147 

REFINING OF RAW SUGAR. 

Raw sugars, with the exception of maple, are now refined 
before being placed upon the market. The refining of sugar was 
not practiced until about 500 A. D. It first appeared in Mesopo- 
tamia and gradually traveled westward, refineries being erected 
in many of the European countries in the 15th and 16th cen- 
turies. In 1689 the first refinery of the Western Continent was 
built in New York City. This industry has gradually grown 
until public taste now demands a pure white sugar. As before 
stated, so far as the beet sugar is concerned, refining is a neces- 
sity since the raw product has a disagreeable odor and taste. 
Cane sugar, however, possesses in the raw state a more fragrant 
odor and agreeable taste than in the refined product. 

Refining sugar is in theory a simpler process than the prepara- 
tion of the raw product, but it requires great care and attention 
to details. Experience has shown that it can only be done eco- 
nomically in very large establishments, which are usually located 
on a navigable river, where the cargoes can be readily received 
and unloaded. Refineries are built many stories high so as to 
take advantage of gravity in passing the solution from one 
process to another. An abundant water supply is also a necessity. 

The process consists essentially in dissolving the crude material, 
separating the impurities and recrystallizing the sugar. 

Outline; of the; Rffining Procfss. — ■ 
I. Raw sugar washed. 

II. Centrifugedj waS l: S / rU P- 

& ( washed raw sugar. 

III. Washed raw sugar melted. 

IV. Defecated. 

V. Filtered through bags j J^^ 6 °" 

VI. Iyiquor bone-blacked. 
VII. Boiled down in vacuum. 

, ( syrup. 

VIII. Centrifuged \ 5™£ \ yellow sugar. 
(. sugar 

Washing. — The raw sugar after being weighed is mixed with 



148 



FOOD INDUSTRIES 



a low grade sugar solution. This process assists in removing 
soluble impurities. 

From the mixing tank, the magma of raw sugar and syrup is 
fed into a centrifuge which is rapidly rotated. The purified raw 
sugar remains on the sides of the basket and the syrup containing 
most of the coloring matter, dirt, glucose and gum passes through 
the perforations. The purified raw sugar is left 99-99^ per 
cent. pure. 

The Melt er. — The washed raw sugar is dissolved in a melting 
tank, which contains steam coils and a revolving arm for stirring. 
When the density of the liquid is about 30 Be., it is pumped into 
defecators or "blow-ups." 




Fig. 43. — Filter Bags. 

Defecators. — Here the solution is treated for the removal 
of such impurities as organic acid and fine suspended matter. 
Different clarifying agents can be employed, such as alum or 
blood albumin. To a large extent now a treatment with calcium 
acid phosphate or phosphoric acid and milk of lime is used. The 
mixture is heated and agitated for about twenty minutes. Soon 
a flocculent precipitate separates out, carrying with it suspended 
matter and some of the coloring. 

Filtration. — The impurities are removed by a mechanical filtra- 
tion through cotton-twill bags enclosed in coarse, strong netting 
sheaths. They are 6-7 feet long and 5-6 inches in diameter. The 



FOOD INDUSTRIES . 1 49 

open end is tied tightly around a metallic nipple by which the 
bag is suspended (Fig. 43). The first run of liquor is often 
muddy and must be refiltered. When the filter bags have become 
exhausted, they are rinsed in several waters. The mud washed 
out contains about 20 per cent, of sugar, part of which can be 
recovered. 

Bone-black Filters. — These filters are large cylindrical iron 
tanks filled with bone-black, a material obtained by the charring 
of bones and reducing them to a granular form by a crushing 
process. Bone-black has the power of decolorizing. About one 
pound is used to one pound of sugar. In passing through these 
filters, the sugar solution loses most of its color, a small amount 
of ash and organic impurities. It is collected in storage tanks ac- 
cording to its color and purity. The char in time loses its power 
of removing color, and must be revivified. It is washed, drained, 
dried, put in a kiln and highly heated to expel organic impurities. 

Vacuum Pan. — The decolorized sugar solution passes to the 
vacuum pan and is then boiled to grain. 

Centrifugal. — After cooling, the separation of the sugar and 
syrup is accomplished by means of centrifugal force. At this 
stage, blue water is sometimes used to give a white appearance 
to the sugar. 

The sugar is dried and passed through screens to separate it 
into grades. It is bagged or barreled to appear on the market 
as granulated sugar. 

Block sugar may be made in two ways. 

I. The boiled mass from the vacuum pan containing syrup 
and crystals of sugar may be drained into conical moulds and 
allowed to stand for about two weeks. It is occasionally washed 
by means of a pure sugar solution. The uncrystallized sugar 
slowly drains off through a small hole opened at the point of 
the cone. The dried sugar is then cut into cubes. A modified 
form of this process, which greatly shortens the time, is now 
being used in Europe and to a slight extent in America. By 
centrifugal force, the cones can be freed in a few minutes from 
the syrup, and the sugar after drying can be cut into blocks. 



I50 FOOD INDUSTRIES 

II. Granulated sugar while still moist can be pressed into 
blocks by an ingenious machine, and gently dried in an oven. 

Powdered Sugar. — Granulated sugar can be reduced to a pow- 
der. When very finely ground it is placed upon the market as 
confectioner's sugar. 

Sugars are coarse grain or fine grain according to the length 
of time allowed in crystallizing. When the operation is slow, 
the crystals are large; rapid crystallization yields small crystals. 

Yellow Sugar. — The syrup obtained as one of the final products 
in the refining process, contains much sugar and can be worked 
over for a second sugar and second syrup. Sugar obtained by 
the treatment of syrups usually appears on the market as light 
brown sugar; darker colors are largely low grade sugars. 

Utilization of the By-Products. — Wherever primitive methods 
for the extraction of cane sugar are used, little thought is given 
to the by-products. This is not true, however, in progressive 
countries where modern machinery and methods are employed. 
Under such conditions, the utilization of waste matter is being 
carefully considered. Such material is obtained as follows: 1st, 
refuse of the beet and cane; 2nd, impurities removed in the clari- 
fying processes ; 3rd, molasses. The beet tops make an excellent 
food for cattle. They may be dried by the sun or with mechan- 
ical means or they may be converted into ensilage. The beet 
pulp remaining in the diffusion batteries, may also be utilized 
as cattle food in the form of wet pulp where it can be used im- 
mediately, in the dried state, or after conversion into ensilage. 
In the cane sugar industry, the leafy portion of the cane top is 
fed to animals, while the begasse has been utilized mainly, in 
the past, for fuel purposes. In recent years, it has been discov- 
ered that an excellent quality of paper may be manufactured 
from begasse. While very little is being done along that line at 
present, the development of paper manufacture in connection 
with this industry, may prove of great importance. 

In both the cane and beet sugar industry, the filter cakes ob- 
tained during the clarifying processes are rich in mineral matter, 
and may be successfully used as fertilizer. 



FOOD INDUSTRIES 151 

Molasses constitutes the most valuable by-product. As it 
contains a large percentage of sugar which cannot be crystallized 
out with ordinary methods, chemical means are being devised 
for its extraction. Beet sugar molasses contains 50 per cent, 
of sucrose. By treatment with calcium, strontium or barium 
hydroxides, it is possible to precipitate the sucrose as insoluble 
saccharate which, after filtration, may be decomposed and re- 
covered as sucrose. Beet sugar molasses being rich in nitro- 
genous and mineral constituents may be utilized for fertilizing 
material with certain kinds of soil. It is also useful as a cattle 
food and for fuel purposes. 

Molasses from the cane industry, may be used as a table syrup 
or for feeding cattle, after being mixed with begasse or such 
material as bran meal or similar products. In both the beet and 
cane sugar industries, the molasses is used largely for the manu- 
facture of rum and alcohol. Lesser products obtained through 
fermentation of cane sugar molasses are acetic, butyric, capry- 
lic and other fatty acids. Many valuable by-products of a nit- 
rogenous nature may also be obtained from beet sugar molasses. 

Maple Sugar. — A sugar and syrup highly prized for confec- 
tionery and table use can be obtained from the maple tree. In 
the United States, they are made almost entirely in Vermont, 
New York, Ohio and Indiana. The process is comparatively 
simple. In the spring, when the sap begins to run, the trees are 
bored and the sap escapes into receptacles. It is usually evap- 
orated in open kettles and allowed to crystallize. The sugar is 
sold in the raw state, as the delicate flavor so much desired is 
lost in refining processes. 

Date Palm Sugar. — In India, the date palm yields a low grade 
crude sugar known as "jaggary." Much of this sugar is shipped 
to England for refining. 

Sorghum. — The sorghum cane belongs to a family of grasses 
resembling the sugar cane. It has been known and valued in 
China for many centuries. Many attempts have been made in 
this country in recent years to extract sugar from the sorghum, 
but without great success. The juice contains dextrin bodies 
n 



152 FOOD INDUSTRIES 

which prevent crystallization of part of the sugar. It is used 
largely, however,' for the production of syrup. The stalks can 
be utilized for the manufacture of coarse wrapping paper and 
the seeds for fodder. 

Cane Syrup. — Cane syrup is prepared largely in small mills in 
our own Southern States by the use of primitive methods. The 
juice of the sugar cane is extracted, clarified, partly inverted and 
evaporated until 25-30 per cent, of the water remains, which is 
sufficient to prevent the crystallization of the sugar. 

Adulteration of Sugar. — With the exception of pulverized sugar 
very little has been found in the United States on account of 
the cheapness of the product. Sugar sold in the powdered form, 
however, has been adulterated from time to time with flour, 
glucose, chalk, silica and gypsum. 



CHAPTER XL 



2. 



ALCOHOLIC BEVERAGES. 

Alcoholic beverages may be classified as follows : 

f Beer. 

I Ale 
I. Malted fermented s -n 1 

J Porter. 

L Stout. 

II. Malted distilled \ Whiskey. 

' i. Sweet or dry. 

P , f Red, Claret, Burgundy, etc. 

{ White, Sauterm, Rhine, etc. 

(' Still, most of the natural wines. 

III. Wines -j 3. CO, -n' Sparkling, Champagne and Sparkling 

( Moselle. 
( Natural, containing not more than 

Alcohol s 15%. Most of the natural wines. 
[_ (_ Fortified, Sherry, Port and Maderia. 

IV. Distilled Wines <j Brandy. 
V. Cordials, L-iqueurs and Gin. 

VI. Sophisticated Wines. 

Historical. — The use of alcoholic beverages dates back to the 
earliest historic times ; hardly a race of men is known even 
among savage tribes which has not its fermented drink. The 
process of beer brewing is of great antiquity, but undoubtedly 
that of wine making is of still earlier origin. It may well be 
imagined that primitive man stumbled upon this process by acci- 
dent. A vessel containing crushed fruit juice, set aside for 
future use, may have been found to contain a drink far more 
exhilarating than the ordinary .fresh fruit juice. Early we find 
that in all countries where fruit could be readily grown, a fer- 
mented drink of this kind was used. Through this simple art 
of wine making, aided by the development of human intelligence, 
the discovery was finally made of how a fermentable sugar could 
be obtained by the treatment of a grain. From that time fer- 
mented grains were used, during seasons when fruit could not 
be obtained, and in regions not adapted to the growing of fruit. 
The art of beer making must have been discovered in early times, 



154 FOOD INDUSTRIES 

for references are made to the beverage in Egyptian records 
dating back to 3000 B. C. It is related that an attempt was made 
by their government to suppress beer-shops over forty centuries 
ago. The Egyptians taught the ancient Greeks and Romans the 
art of brewing, and beer was used as a beverage by the soldiers 
of Caesar's army. Latin authors show that the drink was in 
their time extensively used in Western Europe. The Saxons 
became accustomed to its use before they settled in Britain, and 
for centuries it was used as the national beverage by all English 
people. / 

Beer was prepared from barley, which could be readily grown 
in the British Isles, and was indulged in at every meal by men, 
women and children. A housewife was judged as much by her 
skill in brewing as by the bread that she baked. Families became 
noted for making exceptionally fine beer and recipes were handed 
down in verbal form, from parent to child, and the secret most 
carefully guarded. Beer being a common drink of most of the 
European people before the establishment of the colonies in 
America, it followed naturally that the early settlers brought 
with them to the New World the art of brewing. 

Fermentation. — For the production of alcoholic beverages, the 
manufacturer is as dependent upon the yeast plant as the maker 
of bread. The baker desires carbon dioxide only, while the 
brewer needs for his product, alcohol principally and, in some 
beverages, carbon dioxide also. 

Even under the most favorable conditions, there is a limit to 
the amount of alcohol that yeast can produce. When the alco- 
holic strength reaches 14-15 per cent., yeast can no longer propa- 
gate itself and fermentation ceases. Conditions for its growth, 
such as temperature, food, oxygen and moisture, have been care- 
fully studied in connection with this industry, and modern scien- 
tific research has placed at. the disposal of the brewer of to-day, 
a wealth of knowledge which was not known to his predecessors. 
Most conspicuous among the scientists who made investigations 
along these lines was Louis Pasteur, the father of modern bac- 
teriology. It was from the study of the phenomena of brewing 



FOOD INDUSTRIES 1 55 

that he finally gave to the world the theories of fermentation. 
The study of brewing has contributed much to science, for 
research work has also been done along the lines of: ist, 
processes of germination in seeds ; 2nd, the chemistry of car- 
bohydrates and protein compounds ; 3rd, the action of micro- 
organisms and enzymes. 

Yeast for the brewer's purpose is divided into two groups, 
namely, top yeast and bottom yeast. For its growth top yeast 
requires rather a high temperature — 6o°-8o° F. Fermentation 
is very active; the rapid evolution of C0 2 causes the liquid to 
bubble violently, and as the C0 2 escapes to the surface much of 
the yeast is carried to the top of the vat. This type of yeast is 
used for heavy ales and beers, for alcohol, whiskey and high 
wines. Bottom yeast acts at a lower temperature — 40°-50° F. 
Fermentation is very slow, the evolution of C0 2 is gradual and 
the yeast remains on the bottom of the vat. 

In fermenting at a high temperature yeast generally dies. At 
a low temperature, it can be kept for a considerable time and can 
sometimes be used as a starter for the fermentation of the next 
liquid. Above 86° F., the alcoholic fermentation readily passes 
into the butyric and other forms of decomposition. It is also 
subject to the lactic and acetic ferments. Much study has been 
given to the temperature of fermenting beer. 

Temperature for growth : 

Yeast 32°-i2o° F. 

Lactic ferment 5o -i3o° F. 

Acetic ferment 5o°-i22° F. 

With these facts in mind the brewer on the continent and in 
America uses a low temperature, possibly 48°-50° F. This 
allows the growth of yeast and prevents the development of 
lactic and acetic ferments. 

THE BREWING OF BEER. 

Raw Material. — For the manufacture of beer, water, yeast, 
hops and a malted grain are necessary. The water should be 
free from organic impurities and in general should be moderately 
hard. Continental brewers use a soft water, but in England and 



156 FOOD INDUSTRIES 

America, the presence' of gypsum is preferred. Water contain- 
ing sodium chloride, calcium and magnesium sulphates has been 
found to be very satisfactory. A soft water has a greater solvent 
power on protein, which is likely to undergo decomposition. 
Hops are the catkins of the hop plant. They contain several 
bitter principles which give a desirable flavor to beer. Hops 
also act as an antiseptic. In the early days of brewing, beer was 
always prepared from wheat and barley; later oats, millet and 
anise were sometimes substituted. At the present time, barley 
stands foremost among the cereals used in this industry, on 
account of its flavor and yield of diastase. Rye also occupies a 
prominent position and in Russia and Austria wheat is still 
largely used. In some parts of /the United States, corn under the 
name of grits plays an important part, while rice is used largely 
in the Orient and by American brewers. In Germany, beer is 
often prepared from potatoes. „ 

Processes in the Manufacture of Beer. — 

f 1. Steeping. 

T ,, ,,. J 2. Couching. 
I. Malting j 3 Flooring 8 

I, 4. Drying. 

II. Preparation of the wort. 

III. Boiling 

IV. Cooling ' 

V. Fermentation. 

VI. Preservation 

Malting. — In the classification of the carbohydrates, we find the 
disaccharid maltose C 12 H 22 1;L . This substance is never found 
in nature, in large amounts, as is sucrose and lactose, but must 
always be prepared by allowing the enzyme diastase to act upon 
starch. Here by the process of hydrolysis, starch passes through 
the dextrin stages to maltose. Maltose is, therefore, a partially 
digested carbohydrate and since much of it occurs in beer, that 
beverage contains material of food value, as well as stimulating 
principles. 

Except in very large breweries, malting is now generally 
done by a separate industry. ' This process of changing barley 



FOOD INDUSTRIES 157 

into malt is divided into four stages : steeping, couching, flooring 
and drying. When the barley is received at the malting house, 
dust, dirt, broken kernels and foreign seeds must first be removed. 
This is accomplished by revolving sieves and strong currents of 
air. It is now ready for the processes of malting, during which 
period, the production of diastase is the chief aim of the maltster. 
The mode of formation is not yet known but it occurs during the 
sprouting of the grain. 

In order to soften the grain, it is soaked in water in large 
wooden vats for two or three days, fresh water being added 
from time to time. During this period any imperfect grains 
remaining, will float and can easily be removed by skimming; 
perfect grains gradually sink. This process is stopped when the 
grains have softened so the skin can easily be removed. A test is 
usually made by piercing the grain with a needle. By this time, 
the grain should have absorbed sufficient moisture to allow 
germination to begin so the water is drawn off. The swollen, 
softened grain is couched by being piled in heaps about 24 inches 
deep, on a cement floor, in rooms moderately light. The tem- 
perature is very important, about 6o° F. is maintained, as a high 
degree often causes mold growth. In the olden times, it was 
necessary to carry on this process in the spring and autumn. 
Now malting plants are artificially controlled in temperature, 
so couching can be carried on in any part of the year. The grain 
is kept moist by a frequent sprinkling with water, a good cir- 
culation of air is maintained to supply sufficient oxygen, and it 
is turned from time to time. It gradually begins to "sweat," 
the temperature rises, and an agreeable odor is given off. At the 
end of twenty-four to thirty-six hours, tiny rootlets have ap- 
peared and sprouting has begun. 

By means of wooden shovels it is next spread out on the floor 
in layers of about 10 inches. This is called flooring. To pre- 
vent its heating too rapidly, every few hours it is turned over so 
new grains are exposed ; frequent sprinkling keeps it moist. 
From six to twelve days, the tiny rootlet called "the acrospire" 
is allowed to grow. During this time, two important ferments, 



158 



FOOD INDUSTRIES 



diastase and peptase, -have been formed. The production of 
diastase increases as germination proceeds until it reaches a maxi- 
mum, then it begins to decrease. It is at the maximum stage 
when the sprout has grown three-quarters of the grain. The pro- 




Fig. 44.— Roller Mill for Grinding Barley Malt. (Courtesy of United States 
Brewers' Association.) 



cess is then stopped. As soon as the diastase is formed it begins 
to act on the starch of the barley, gradually changing part of it 
to dextrin and maltose. 

Germination is stopped by drying. This may be accomplished 



FOOD INDUSTRIES 



159 



by air-drying or in a kiln. The character and odor of the beer 
are much influenced by the method of drying. A low tempera- 
ture produces a pale malt, higher heat gives yellow, amber and 
brown. After drying, the rootlets are brittle and can easily be 
removed by passing the grain through sieves containing rotary 
brushes. The grain is now called barley-malt. 

The Wort. — The preparation of the wort or the mashing 
process is the second stage in the making of beer. The malt is 




Fig. 45. — Filter Presses for Clarifying the Wort. (Courtesy of United States 
Brewers' Association.) 



cleaned and coarsely ground in a roller mill (Fig. 44), and a 
water extract is made. Another cereal such as corn or rice may 
be added. This process is intended not only to extract the dex- 
trin and maltose already formed, but to allow the diastase to 
act upon any starch present so it may be converted into dextrin 
and maltose. Peptase is also active, converting protein matter 
to the more easily digested form of peptone. Great care is given 



i6o 



FOOD INDUSTRIES 



that the temperature be kept at the point where the diastase and 
peptase can do the most effective work. Tests are made from 
time to time with iodine. After a certain length of time the 
watery extract is drawn off and fresh water is added. This is 
called the second extract. Again a third extract may be made. 
These extracts when mixed are passed through a filter press 
(Fig. 45). They are known as the wort. The wort contains 
dissolved material which has been acted upon by ferments. 




Fig. 46.— Copper Boilers. (Courtesy of United States Brewers' Association.) 

Boiling. — The wort is run into copper kettles where it is boiled 
from one to two hours (Fig. 46). Hops are added during this 
time. The boiling accomplishes several desirable changes: 1st, 
Unchanged protein coagulates and separates out. This change 
is assisted by tannic acid dissolved from hops. 2nd, The wort 
is concentrated and sterilized. 3rd, The constituents of hops 
are taken up by the wort. They give taste, aroma and keeping 
quality to beer. 



FOOD INDUSTRIES l6l 

Cooling. — After boiling, the temperature- must be dropped 
rapidly to prevent undesirable fermentation from starting. This 
is accomplished by running the boiling hot liquid into cooling 
tanks, then passing it quickly over pipes through which brine is 
being circulated. It is cooled down to a temperature of 40 F., 
the point needed for the fermentation by yeast. 

Fermentation. — For a long period, fermentation of the wort 
took place in great open vats made of oak It was le'ft for spon- 
taneous fermentation or more often yeast was added. Recent 
experimentation has proved that fermentation is far more satis- 
factory when carried on in closed iron vats lined with porcelain, 
through which filtered air is forced. In the use of the closed re- 
ceptacle, pure yeast cultures may be utilized with great efficiency. 
As bottom fermentation is used in America, the temperature is 
kept below 50° F. This method produces less alcohol but the 
flavor of the beer is considered better. In England, top fer- 
mentation is more popular. It requires a higher temperature, 
65°-8o° F., the action is rapid and more alcohol is developed. 

I. Main fermentation lasts from 4-8 days, when a high tem- 
perature is used; and from 9-10 days in bottom fermentation. 
During this period, new yeast cells are constantly forming and 
in their desire for food are breaking down sugars into alcohol, 
carbon dioxide, glycerine and succinic acid. As the action goes 
on, there is a tendency for the temperature to rise. It was cus- 
tomary in olden time to float in the vats, cans containing ice. 
As most modern breweries have a cooling plant, brine is circulated 
through coils in the bottom of the vats. By these means the 
desired temperature can be maintained. At the end of this pro- 
cess, it is called the "new beer." 

II. For the after fermentation the new beer is drawn from 
the vats into casks containing beech wood shavings, which have 
been passed through a sterilizing process. Isinglass can also be 
used. These assist in clarifying the beer. The temperature is 
kept low, the yeast cells gradually cease growing and in settling, 
become attached to the shavings, leaving the beer clear. 

III. The storage fermentation takes place in casks and lasts 



1 62 



FOOD INDUSTRIES 



from three to six months. During this time flavor is developed. 
Fresh beer is added to give the product its head and fermentation 
goes on slowly at a low temperature, after which the beer is ready 
to be filtered and bottled or barreled (Fig. 47). 

Preservation. — Pasteurization is sometimes used and is a per- 
fectly legitimate method of preserving beer. The temperature 
is raised to 140 F., which is high enough to kill any ferment 
present. 




Fig. 47.— Filter Presses for Clarifying Beer before Bottling 
United States Brewers' Association.) 



(Courtesy of 



Great care must be given to the bottling and barreling process. 
The barrels are usually coated on the inside with pitch and are 
regularly inspected. They may be disinfected with S0 2 or thor- 
oughly sterilized with live steam and rinsed with filtered water. 

Any carelessness at this stage causes the souring of beer. The 
keeping qualities depend on absolute cleanliness in barreling or 



FOOD INDUSTRIES 1 63 

bottling, purity of the water and yeast, and the quality of the 
grain and hops. Sanitary conditions should be maintained 
throughout brewing. 

The use of preservatives such as silicylic acid or boracic acid, 
is forbidden by many countries. 

Composition of Beer. — Beer contains when ready for use dex- 
trins, maltose, peptones, alcohol Z~7V2 P er cent., and carbon di- 
oxide. The addition of hops gives tannin, volatile oils which 
give a better flavor, alkaloids which have a narcotic effect, and 
resins which contain antiseptic principles and protect against 
undesirable fermentation. Bitter substances have been added to 
give pungency, as quassia, gentian root and ginger, but their use 
is now prohibited by most governments. 

Adulteration. — The adulteration of beer is of early origin. In 
1620 mention is made that cocculas indicus was used in Holland 
and during the reign of Queen Anne, of England, it was necessary 
for Parliament to pass a law prohibiting brewers from using 
this substance, as well as other unwholesome ingredients. One of 
the earliest books written on food adulteration, exposes the prac- 
tices of the brewers of the early 19th century. Such substances 
as ground alum, coloring matter, beans, quassia, capsicum, cara- 
way seeds, grains of Paradise, strychnine and picric acid were 
frequently used. Beer many times was prepared from chemical 
preparations, substituted for malt and hops. 

While much has been said against the brewer of modern times, 
it is safe to say that adulteration has practically disappeared in 
this industry. There is a prevailing belief that beer contains a 
variety of substances such as opium, belladonna, strychnine and 
corrosive acids, but these ideas are not true. The only harmful 
ingredients are preservatives. Sodium bicarbonate is sometimes 
used to overcome acidity and to increase the head. 

Substitution. — Beer is generally supposed to be made from 
barley malt. This operation is long and involves a certain 
amount of waste so is expensive. Brewers sometimes substitute 
glucose. This is practically the same practice that is found in 



164 FOOD INDUSTRIES 

malted breakfast foods. It is not, however, injurious if the 
glucose is a pure article. 

Kinds of Beer. — Lager beer is used in Germany and to a great 
extent in America. It is always made by bottom fermentation, 
where the process is allowed to proceed slowly and has, therefore, 
less alcohol, but a more desirable flavor and better keeping qual- 
ities. Lager means stored, so this variety of beer is always stored 
six months. It is brewed in the winter and stored until the fol- 
lowing summer. There is usually the addition of a large amount 
of hops. 

Ale is a light colored beer made by top fermentation. It has, 
therefore, more alcohol, about 7^ per cent. The bitter flavor is 
due to the addition c*f more hops than in ordinary beer. It is 
practically the only beer made in England, as they use top fer- 
mentation. 

Porter is a dark colored beer. When a high temperature is 
used in kiln-drying malt, the carbohydrates present become par- 
tially charred and caramel is formed. This gives color and flavor 
to the beer. Porter contains about 5 per cent, alcohol. 

Stout is a porter with a higher percentage of alcohol usually 
about 7 per cent. It contains more of the extracts. 



CHAPTER XII. 



ALCOHOLIC BEVERAGES. (Continued.) 



THE WINE INDUSTRY. 

Wine is the fermented juice of a fruit which contains sugar 
or its derivative invert sugar. While any sweet fruit may be 
used, the term wine generally refers to the juice of the grape., 
for that is the only fruit which is cultivated on an extensive 
scale for the manufacture of wine. Grapes owe their wine pro- 
ducing value to several important constituents: 1st, the large 
amount of grape sugar which often constitutes 18-20 per cent, 
of the weight of the fresh fruit and more than half of the solid 
matter; 2nd, the organic acids of which tartaric is the most im- 
portant; 3rd, the proteins which greatly influence fermentation. 

The cultivation of the grape for this purpose began in the 
Orient, and gradually extended into the middle and south of 
Europe, and into the northern part of Africa along the countries 
bordering on the Mediterranean. France, Spain and Portugal are 
now the chief wine producing countries of Europe, although 
along the banks of the Rhine and Moselle Rivers as well as other 
parts of Germany, Austria and Italy, grapes are cultivated in 
large quantities. The islands of the Atlantic and certain sections 
of America, as California, New York, Ohio and Virginia, are also 
important wine manufacturing centers. The climatic conditions 
and the character of the soil greatly influence the quality of the 
grape. The vine grows on soil containing mineral matter, chalk, 
magnesia and silica. It appears to thrive best along the borders 
of rivers and on ground which can attract considerable moisture 
from the subsoil. The composition varies from season to season 
due to weather conditions. A warm summer with a moderate 
amount of rain gives the highest percentage of sugar and tar- 
taric acid. During a cold, rainy, grape growing season, less 
sugar is produced and a higher percentage of malic acid is 
developed. 

The varieties are very numerous and there is great difference 



l66 FOOD INDUSTRIES 

in the cultivation in various localities, but wherever grapes are 
grown for the wine industry, great care and experience are 
absolutely essential. 

Processes in the Manufacture of Still Wine.— 
I. Grapes picked when fully ripe. 
II. Crushed between rolls or with the feet. 
III. Pressed or centrifuged. 

5 Active. 
Still. 
Storage. 

Picking. — Grapes are taken for wine making either when ripe 
or slightly over ripe, according to the character of the wine. 
The harvesting usually begins early in September and continues 
into November. The early grapes usually contain the largest 
amount of sugar, but those taken later in the season when al- 
lowed to become over ripe, produce a wine having a peculiar 
bouquet which is much prized. 

The grapes are picked by hand or with a fork. Except in 
certain districts, the common practice is to gather all the grapes 
carried by the vine and to sort them into grades. The care given 
in sorting, differs greatly according to the quality of the wine. 
For the finest wines, all unripe, bruised, sun-burned and rotten 
grapes are discarded. In the manufacture of red wine, the stems 
are also removed by causing the grapes to pass through a series 
of sieves by which the stems are retained. The almost universal 
practice in white wines is to allow the grapes to remain upon the 
stems during the pressing, as the separation of the must and 
marc takes place before the astringent principle which they con- 
tain can be communicated to the must. 

Extraction of the Juice. — In order to extract the juice, the 
grapes must first be softened. This may be accomplished by 
treading underfoot in vats or by crushing between grooved roll- 
ers, great care being taken that the pressure be gentle, so that 
the juice from the pulp only will be extracted. Heavy pressure 
forces the juice from the skins and bruises the seeds and stems if 
these have not been removed. This greatly injures the flavor 



FOOD INDUSTRIES 1 67 

of the wine. Treading with the feet has probably been the most 
satisfactory method. Wooden shoes are now worn as they are 
more sanitary and give a gentle even pressure. The softened 
grapes are pressed or passed through a centrifugal machine. At 
this stage, for white wines, the skins are removed if the blue 
grapes are being used. If red wine is wanted, the skins are left 
on. After pressing or centrifuging, the juice is known as the 
"must" and the pulp and skins as the "marc." The quality of 
the wine depends on the "must." The first portion is often col- 
lected separately as it is the juice of the ripest and sweetest 
grapes. That which is pressed from the grapes later contains 
more acid and tannin, for it is obtained from the unripe grapes 
and skins. 

Fermentation.- — The fermentation of red wines usually takes 
place in large open vats of wood, marble or stone. White wines 
are generally fermented in barrels with only the bungholes opened 
for the escape of the carbon dioxide generated. Although the 
use of yeast cultures has recently been introduced in certain 
localities, fermentation is still almost always spontaneous in the 
wine industry. Spores of the wild yeast are always present on 
the skins of grapes and in the air of grape producing regions, so 
fermentation begins at once. A temperature of about 50 F. 
is maintained for bottom fermentation and jo° F. if top fer- 
mentation *is desired. 

Fermentation is divided into three stages. 

I. Main fermentation. — During this period the yeast cells are 
very active, the- liquid becomes turbid, carbon dioxide is given 
off, a scum forms and a sour taste and odor are developed. Tt 
lasts from one -to three weeks according to the temperature used. 
When .fermentation is completed, the evolution of gas ceases, 
yeast cells and other suspended matter settle to the bottom and 
the liquid becomes clear. During this process the proteins are 
largely consumed by the yeast. 

II. Still Fermentation. — The new wine is run into tungs or 
casks where it remains until the following spring. During this 
after fermentation the young wine slowly loses its sugar and 



1 68 FOOD INDUSTRIES 

remaining protein substances. Acid potassium tartrate and cal- 
cium tartrate separate out and form deposits known as argol and 
lees. For further .information see Chapter VIII, Leavening 
Agents. 

III. Storage Fermentation. — The storage of wine lasts for 
many years according to the quality. Very rich wines are held 
for eight years or more, cheaper varieties from two to four. Dur- 
ing this process of ripening the desired bouquet is gradually de- 
veloped. This is due to the formation of etheral salts, from the 
alcohols and organic acids present in the wine. Minute quanti- 
ties of higher alcohols known as fusel oil are developed during 
fermentation. As they are of a poisonous nature, the formation 
of these salts not only means the development of desirable fla- 
vors but the lessening of the toxic quality of the wine. Tannins 
and other impurities are gradually precipitated. Sometimes dur- 
ing the ripening process clarifying agents such as gelatin and 
albumin are added to assist in dragging down suspended mat- 
ter. The treatment with gelatin is particularly applied to sweet 
and heavy white wines which frequently remain more or less 
turbid. Albumin as a rule is used with red wines which contain 
tannic acid. 

Improving Wines. — The juice pressed from the grape varies 
in composition to a considerable extent from year to year, ac- 
cording to the amount of rain fall, sunshine and temperature. 
As a result it is usually treated or improved in some way to 
maintain certain proportions. The must of a poor season can 
be so treated as to bring it up to the standard of a must of a 
good year, by correcting the ratio of acid to sugar. Any excess 
of acidity may be overcome by neutralizing with marble-dust and 
the addition of a certain quantity of cane sugar. To improve 
the sweet, taste without injuring the keeping qualities glycerine 
is sometimes added. Wine deficient in alcohol and containing 
a large amount of acid is frequently improved, by the addition of 
wine of a succeeding year. The practice of adding gypsum or 
plaster of Paris has prevailed extensively in the countries of 
south and south-western Europe. This is known as "plastering," 



FOOD INDUSTRIES 169 

and is supposed to have for its object the withdrawal of a cer- 
tain amount of water from the must, thus increasing the alcoholic 
strength. It also deepens the color and adds to the keeping 
qualities. Public opinion is strongly against the custom, how- 
ever, as it is supposed to have an injurious effect on the con- 
sumer of the wine. The process is now controlled by law. 

In certain heavy wines as Port and Madeira, alcohol is added 
and they are known as fortified wines. The amount of alcohol 
developed during fermentation never exceeds 12-13 P er cent. 
Alcohol is added to fortified wines until the strength reaches 
16-22 per cent. 

CHAMPAGNE. 

V/The art of making champagne was discovered by a monk dur- 
ing the 1 8th century. Both white and red grapes are used and 
a special treatment is necessary. Great care is given in picking so 
that the grapes are not crushed, or coloring matter may be added 
to the juice. The branches are detached one by one and care- 
fully sorted according to their ripeness. In some localities even 
the individual grape is examined. After picking they are crushed 
quickly in order to prevent any coloring matter being taken up. 
The first press only is used for champagne, the second and third 
being utilized for cheaper wines. After the must has been al- 
lowed to stand long enough for impurities to settle, it is run im- 
mediately into casks for the main fermentation, which usually 
takes place in cool cellars. The young wine is allowed to fer- 
ment until the early winter, when it is cleared with isinglass and 
racked off into other casks. At the end of one month this opera- 
tion is repeated. Before bottling it is mixed with a certain 
proportion of old wine and cane sugar. The bottles are then 
placed in a horizontal position in champagne vaults, where they 
remain six months or longer. New fermentation starts, much 
C0 2 is developed and a quantity of sediment is formed. This 
scum can later be removed by first placing the bottles in an 
inclined position so impurities will gather near the cork, which is 
then carefully removed just long enough to allow the sediment 
to be blown off. By chilling the bottles just before the opera- 



170 FOOD INDUSTRIES 

tion, the pressure is reduced and the cork can be liberated with 
very little trouble. The loss in the bottle is replaced quickly by 
sugar, fine wine and aromatic essences, and the bottle is again 
corked and wired. Champagne is usually held for a period in 
order to allow blending and ripening to take place before it is 
placed upon the market. 

An imitation champagne is sometimes made by forcing carbon 
dioxide into a sweet white wine to which liqueur has been added. 

Sophisticated Wines. — The so-called sophisticated wines are 
prepared by mixing water, alcohol, tannin, sugar, tartaric acid, 
fruit essences and the like, closely imitating the composition of a 
regularly fermented wine. 

Composition of Wine. — Wine contains water, alcohol, glycerine, 
ethereal salts, and other volatile products giving flavor and 
bouquet, grape sugar, tartaric and malic acids, mineral matter, 
pectin, gummy matter and, tannin. 

Adulteration. — The practice of adulterating wine is almost as 
old as the wine industry. The ancient Greeks and Romans were 
forced to pass strict laws to prevent such practices, and officials 
were appointed to detect and punish those who adulterated wine. 
Substitution and adulteration are still being carried on exten- 
sively. Innumerable substances have been added — water, glyc- 
erine to give sweetness, coloring agents such as berries, beets, coal 
tar products and holly-hocks, flavoring to make inferior wines 
appear older and better grade, cloves, bitter almonds and elder- 
berry juice. In France, on account of the failure of the wine 
crop in recent years, a wine has been made from dried raisins 
and prunes and substituted as grape wine. Raisin and prune 
wine is a perfectly legitimate product only when sold under its 
own name. 

By-Products.- — Cheap wines are prepared by adding water and 
sugar to the marc and fermenting it. This wine is largely used 
by the poorer people on the continent. The marc may also be 
utilized in the production of cheap brandy and vinegar, as a fer- 
tilizer, for fuel purposes and for cattle food. 

In Europe tannic acid is extracted. This is used extensively in 



FOOD INDUSTRIES 171 

the textile industry. The preparation of cream of tartar from 
argol is another important industry connected with wine making. 
Preservation. — Pasteurizing and the use of preservatives are 
practiced in this industry similar to the processes described under 
beer making. 

DISTILLED LIQUORS. 

Distilled liquors differ from malted beverages such as beer, 
ale, porter and stout, and from products of the wine industry, 
in two important ways : 

I. In the fermentation process, every effort is made to have a 
maximum amount of alcohol developed. 

II. The fermented liquid is distilled and redistilled in order 
to have a product rich in alcohol. 

There are three classes of distilled liquors. 

I. Brandy. — The first class of distilled liquors uses as a basis 
wine which when distilled produces brandy. The product con- 
tains much of the flavor and bouquet of the original wine. Fic- 
titious brandy may be made from grain or potatoes, but a true 
brandy is always manufactured from the fermented juice of a 
fruit. Apples, peaches, plums, cherries and blackberries may be 
used, but by far the largest amount is produced from the grape. 

The brandy industry has been chiefly carried on in France, 
particularly in the southwest districts, where the product is 
known as cognac. The vineyards in this part of France have 
suffered greatly in recent years and the making of imitation 
cognac is greatly increasing. 

A very inferior grade of brandy is sometimes made by adding 
water to the marc, fermenting and afterward distilling the 
product. 

II. Rum. — A sugar-containing material such as molasses is 
always utilized in the production of rum. This industry is car- 
ried on very largely in close proximity to sugar cane and sugar 
beet factories, which readily supply the raw material in the form 
of molasses and sugar scums. The East Indies and the West 
Indies, especially Jamaica, use enormous quantities of molasses 
from the cane in this way. In the West Indies, rum is always 



172 FOOD INDUSTRIES 

flavored with caramel. The beet sugar industry also supplies 
much molasses for this purpose especially in France and Ger- 
many. For the production of rum, the sugar-containing material 
is diluted, fermented and distilled until the product contains 
approximately 55 per cent, of alcohol. 

III. Whiskey.- — In the manufacture of whiskey a starch-con- 
taining material, for example a cereal, is used as a basis. It is 
malted, fermented and distilled. The cereal used as raw material 
depends entirely upon the country. England uses barley, wheat 
and oats and the United States, corn, rye and barley. Scotch 
whiskey is usually made from malted barley which was formerly 
dried in a kiln and heated by glowing peat. A peaty flavor was 
imparted and retained by the final product, which gave to Scotch 
whiskey a characteristic aroma and taste that were highly prized. 
Now, peat is scarcely used so creosote is added to give a similar 
flavor. In Russia, wheat is largely used giving a whiskey known 
as "vodka." Germany uses the potato almost exclusively for this 
industry. 

Distillation. — In distilling these products, advantage is taken 
of the different boiling point of alcohol and water. At a tem- 
perature o"f 78°-8o° C. alcohol will volatilize carrying with it 
whatever is volatile. The still may be very simple in construc- 
tion with the same principle as the water-still or it may be very 
complicated. A process known as fractional distillation is quite 
extensively used. The hot vapor is chilled by coming in contact 
with metallic diaphragms, where a portion condenses and can be 
separated from the richly alcoholic vapor, which passes on to 
another compartment. The stills are frequently columnar in 
shape, and are divided into compartments by horizontal copper 
plates, perforated with holes, and furnished with valves opening 
upward. Dropping pipes are attached to each plate, and are 
connected at their lower end with shallow pans. When the still 
is in operation, the fermented liquid, heated to the vapor state, 
is allowed to enter the lowest compartment. As it rises, the 
vapor comes in contact with a metallic diaphragm which lowers 
the temperature, thus causing part of the water content to con- 



FOOD INDUSTRIES 173 

dense and drop back through the pipe into the shallow pan. The 
alcoholic vapor passes on to the compartment above where the 
temperature is again lowered, causing more water to condense. 
The operation is continuous and can be carried on until the per- 
centage of alcohol is raised as high as 95 per cent. This high 
figure is only used in the production of 95 per cent, alcohol. 
Higher than this can only be obtained by chemical means. Four 
per cent, of the water may be removed by lime and the remaining 
one per cent, by metallic sodium. The product is then known as 
absolute alcohol. In the distillation of fermented liquids for 
alcoholic beverages, a strength of about 45 per cent, is usually 
obtained, although it may vary from 30 to 60 per cent. 

Bonded Whiskey. — While the chief constituent of whiskey is 
ethyl alcohol, when freshly made it also contains small quanti- 
ties of higher alcohols, fatty acids and other volatile products 
known as fusel oil. As these products are considered injurious, 
whiskey is put in storage under government protection for five 
years. During the process of aging, chemical changes take 
place. Through oxidation, ethers are formed from the fusel oil 
which give aroma and bouquet. Whiskey is, therefore, improved 
in two ways by storing: 1st, it loses toxicity; 2nd, it gains 
in flavor. As oak barrels are always used for storage, a certain 
amount of tannin and coloring matter is extracted from the oak 
by the action of the alcohol. 

CIDER. 

Cider may readily be regarded as a wine since it is the fer- 
mented juice of the apple. It is made extensively wherever that 
fruit can be readily grown. Cider is manufactured for use as a 
beverage and as a foundation for what is regarded in the United 
States as the best kind of vinegar. The fruit is chopped and 
crushed in a mill, and the extracted juice is run into barrels, where 
it is allowed to ferment. Where the same care is given as in the 
preparation of wine from grapes, the product is a superior grade 
and has good keeping qualities. The greater part, however, pro- 
duced in this country has a very short life, owing to the poor 
quality of the raw material and to carelessness in manufacturing 



174 FOOD INDUSTRIES 

processes. The apples used are often those not marketable on 
account of small size, bruises, greenness or decay, the perfect 
fruit as a rule being used, only when the crop is so large that it 
pays better to make cider than to sell the apples at a low price. 
Poorly made vinegar is frequently adulterated with salicylic acid. 
Cider is mildly alcoholic in its nature, containing in the sweet 
stage about I per cent, and as it ages from 3 to 5 per cent, 
alcohol. In hard cider 8 per cent, alcohol is frequently found. 
Sugar, organic acids of which malic predominates, salts and 
extractives are also present, the latter giving odor and taste. 

VINEGAR. 

Vinegar is a product obtained by the fermentative action of a 
group of bacteria, on a sugary solution which has undergone 
alcoholic fermentation, such as cider, wine, malted products and 
the like. The micro-organisms cause the oxidation of the alcohol 
into aldehyde and ultimately into acetic acid according to the 
following equation : 

C 2 H 5 OH + O — CH 3 CHO + H 2 0, 
CH3CHO + O — CH3COOH. 

In this country cider or wine vinegars are preferred, while in 
England malt vinegar is largely used. Until recent years, cider 
vinegar was obtained by allowing barrels partly filled with cider 
to remain standing in a warm cellar for a number of months, the 
bungs being left open. This process was so long, however, that 
it has now been almost entirely replaced by what is known as 
the "quick vinegar process." Cider is allowed to percolate slowly 
through perforated casks filled with twigs or shavings, which 
have been saturated with old vinegar. By this method the 
product is ready for use in a short time, but the best varieties 
undergo a process of aging before being placed on the market. 

In wine producing sections, vinegar is prepared from cheaper 
grades of wine and from wines which have spoiled by the acetic 
ferment having set in. White wine vinegar is usually consid- 
ered the best. It contains a little more acetic acid than cider 
vinegar, also tartaric acid and some of the mineral salts of the 
grape as acid potassium tartrate. 



FOOD INDUSTRIES 175 

Cider vinegar has 4^2 to 5^ per cent, acetic acid and marked 
traces of malic acid which has come from the apple. Mineral 
matter, sugar and extractives are also present, the total solids 
constituting about 2 per cent, of the entire weight. 

As England is neither a wine nor cider producing country, it 
is customary to make vinegar from a malted product as the wort 
of beer, the addition of hops being omitted as they possess an 
antiseptic effect. Such a product is dark in color and has con- 
siderable extracted matter such as dextrin, maltose, protein, min- 
eral matter and extractives. The percentage of acetic acid is not 
as high as in wine and cider vinegar, therefore, a small amount of 
sulphuric acid is frequently added, 0.1 per cent, being allowed 
by law. 

Vinegar may also be made from sugary solutions as molasses 
or by synthetic processes. Synthetic vinegar is v the nearest 
approach to pure acetic acid, but as it contains less dissolved 
material, it lacks flavor. 

Adulteration. — Vinegar has been largely subject to substitution 
and imitation. The best varieties on our market are cider, wine 
and malt vinegar. Substitution may be detected by slowly evapo- 
rating almost to dryness 100 cubic centimeters of vinegar and 
examining the warm residue. That of cider vinegar will give a 
distinct odor of baked apples and will respond to the malic acid 
test. The residue of wine vinegar contains tartaric acid and has 
the aroma of the grape. Malt vinegar gives a malt odor, distilled 
vinegar that of burnt sugar, while no residue on evaporation 
indicates a synthetic product. 

KOUMISS. 

Koumiss is a fermented drink used largely in Russia and by 
Asiatic tribes. It was originally fermented mare's milk, but for 
American purposes cow's milk is usually employed. The process 
is started by adding yeast cultures and a small amount of sugar 
syrup to milk or by mixing fresh milk with some already soured. 
Both the lactic and alcoholic fermentation are started and con- 
tinue for twenty-four hours. The result is a slightly sour milk 
containing alcohol and carbon dioxide. It is much used by 
invalids and people with weak digestion. 



CHAPTER XIII. 



FATS. 



For information in regard to the source, composition and 
properties of fats, see Chapter I, Food Principles. 

Extraction. — The methods for the extraction of fats differ ac- 
cording to the physical condition in which they exist, their source 
and use. 

Animal fats are contained in cells composed of membranous 
tissue, which putrifies soon after the animal is killed, causing the 
fat to become rancid. It must, therefore, be extracted or rendered 
immediately to prevent a foul, odor from arising. Solid fats like 
tallow or lard are freed from the enclosing membrane by finely 
chopping the material, subjecting to low heat and drawing off 
the fat in the melted state. Great care is necessary that the 
product is not overheated, lest the neutral fat be decomposed 
into fatty acid and glycerine. The temperature should not exceed 
130 C. The heating may be done in open kettles over direct 
flame, either with or without the addition of a small amount of 
sulphuric acid, or by the action of steam under pressure. 

The vegetable oils are found to exist in largest quantities in 
seeds and nut's. In order to extract the oil, they are carefully 
cleaned, crushed to break the shell or kernel and ground to a 
fine powder. Crushing is carried out in machines called the oil 
seed mill, some types of which are of great antiquity. The oil 
can then be removed by pressure or by the use of a solvent. With 
pressure, heat may or may not be added. Hot pressing gives a 
larger yield, but a better product is obtained with the cold 
method. Many times the cold process is used first for the extrac- 
tion of the highest quality oil, then heat is added for lower 
grades. 

A larger amount of oil can be obtained by the use of solvents 
such as naphtha, ether and carbon disulphide, but this method 
cannot be used for edible oils. 

Purification. — The extracted oils are in a very crude condition, 
containing suspended and dissolved matter of various kinds and 



FOOD INDUSTRIES 177 

must be purified even if the oil is to be used for manufacturing 
purposes such as soap-making. Purifying can be carried out by 
filtration through cotton- wadding or bone-black, by the use of 
Fuller's earth, by chemical treatment or by a bleaching process. 

BUTTER. 

One of the most easily digested fats is butter. It has been 
used as a food since the days of the early Hebrews, but during 
the Greek and Roman civilization it appears to have been utilized 
only as an ointment. 

The original method of making butter was very simple. Whole 
milk was put in a bag prepared from animal skins and the mass 
was agitated until the butter appeared. This involved a great 
amount of labor and a considerable loss of fat, so in time the 
separation out of the fat by the method known as creaming came 
into use. 

Composition of Butter.— 

Water ... 12 — 16% f Butyrin. 



Fat 82.5 + fy \ 



( 1. Soluble 10% ! Caproin. 
I Caprylin. 
i. Caprin. 

f Olein. 
j Palmitii 
( Stearin. 



! C Olein. 

1^ 2. Insoluble 90% -< Palmitin. 



Protein trace \ Caseinogen. 

Carbohydrate . . trace <J L,actose. 

,,. , „, f Sodium chloride. 

Mineral matter 2% j ^ of ^ 

The object in butter making is to extract from milk its fat, 
which exists in an emulsified form. The United States Standard 
butter requires at least 82.5 per cent, fat and not more than 
16 per cent, water. The fat consists largely of palmitin, olein 
and a small amount of stearin, mixed, not chemically combined, 
in about the same proportion as found in lard. In addition 
to these non-volatile fats, there exists in small amounts, various 
volatile fats which give to butter its characteristic taste and 
aroma. The most important are butyrin, caproin, caprylin, and 
caprin. 



178 FOOD INDUSTRIES 

Processes in Butter Making. — 

, p ., ( Shallow pan. 

j * ^ { Deep setting system. 

I. Separation of the cream <j 

1 

t. 2. Centrifugal force. 

II. Ripening of the cream. 

III. Churning. 

IV. Washing. 
V. Working. 

Separation of the Cream. — The separation of fat from milk, 
from the earliest times to comparatively recent years, was accom- 
plished by the gravity method. This was called "gravity cream- 
ing." As fat exists in the form of an emulsion, by allowing milk 
to rest, the globules will gather near the surface of the liquid. 
In so rising, they carry with them certain of the milk constituents 
such as minute particles of milk sugar, caseinogen and mineral 
matter. The earliest idea in creaming was the use of the shallow 
pan, and although rapid changes have been made of late years, 
a large quantity of butter is still being made by this method. As 
quickly as possible after milk has been drawn from the cow, it 
is run into shallow pans, cooled and placed in a clean, well venti- 
lated cellar where it is kept about thirty-six hours at a tempera- 
ture approximating 60 ° F. After the fat has gathered at the 
top, it is removed by a skimmer. With this method the separa- 
tion is imperfect, as about 20 per cent, of the fat remains with 
the skim milk. 

The use of deep pans for creaming has been very popular in 
many parts of Europe for the past thirty years. The tempera- 
ture of the milk is rapidly dropped to 40 F. where it is main- 
tained by ice or cold water from twelve to twenty-four hours. 
This insures a more perfect separation of the cream, the loss 
involved under favorable conditions being less than one-half the 
amount which occurs in the shallow pan method. 

In the United States the deep setting system has never been 
largely employed. This is undoubtedly due to the fact that 
shortly after its introduction abroad, a machine was patented by 



FOOD INDUSTRIES 



179 



which fat could be removed from milk by centrifugal force. 
Although the cream separators, as they are called, were at first 
very crude, it is to their development that we owe revolutionizing 
methods in butter-making (Fig. 48). In separating cream by 
this method, much labor is saved and less loss is involved. The 
separator consists of a revolving bowl or drum usually made of 
cast iron. Old-fashioned types have hollow drums, but modern 
separators contain contrivances in the bowl to increase the effi- 
ciency of separation (Fig. 49). An entrance is made for the 
whole milk and suitable openings for the removal of the cream 




Fig. 48. — Early Experiment in Cream Separator. 
(Courtesy of the De Laval Cream Separator Co.) 

and the skim milk. When the bowl is rapidly revolved, the 
heavy liquid is thrown toward the outer wall from where it 
finds an exit through the skim milk tube. The cream being 
lighter moves toward the center and is drawn off through the 
cream outlet. The separation can be carried almost to perfect. 
The cream separator also assists in clarifying milk, as much 
dirty material is thrown against the outer wall of the bowl, and 
can be removed from the skim milk by screening. 

Ripening of the Cream- — It is possible to make butter directly 
from sweet cream, but such a product lacks the delicate flavor 
and texture of butter which has passed through a ripening pro- 



i8o 



FOOD INDUSTRIES 



cess, and it does not keep as well. This process is essentially the 
holding of cream under favorable conditions for a period, in 
order to allow bacterial action to take place. Such action may- 
be brought about by bacteria of the air or those natural to milk, 



SIMPLE CREAM SCREW 
ADJUSTMENT 



SIGHT FEED LUBRICATOR 
(SOLE OIL SUPPLY) 



CENTER BALANCED BOWL 



SPLIT-WING TUBULAR 
OR FEEDING SHAFT 



ONE PIECE DETACHED SPINDLE 



SEAMLESS ANTI-SPLASH 
SANITARY SUPPLY CAN 



SANITARY FAUCET 

EXTRA HEAVY TINWARE 

REVERSIBLE FLOAT 



HIGH BEARING CASE PROTECTING 
GEARS FROM MILK AND WATER 



HELICAL TOOTH SPUR. PINION 
AND WORM WHEEL GEARS 



BRONZE REVERSIBLE WORM WHEEL 
FRAME JOINING SCREW 
OPEN. SANITARY BASE 




Fig. 49.— Improved De Laval Cream Separator. 
(Courtesy of the De Laval Cream Separator Co.) 



causing the development of lactic acid. The temperature during 
this process is regulated from 6o°-70° F. and absolute cleanli- 
ness has been found to be essential. Any carelessness at this 
stage is apt to cause other ferments to work upon the milk and 



FOOD INDUSTRIES IOl 

undesirable flavors to be developed. In order to have a uniform 
taste to butter, the cream is sometimes pasteurized, cooled and 
artificial bacterial cultures are added. Their use was first sug- 
gested by the people of Denmark, who now employ this process 
largely. Professor Conn, of Wesleyan University, also highly 
recommends their use, but they have never been as popular in 
America as they have been abroad. The majority of experts prefer 
the flavor of butter which has been ripened naturally under 
thoroughly sanitary conditions. 

The amount of acid allowed to develop depends on the taste 
desired. Experienced butter-makers usually judge by the appear- 
ance and flavor or tests can be made for acidity by the use of 
normal alkali solutions. Under-ripening gives an insipid tasting 
product, while over-ripening causes the development of unde- 
sirable flavors and gives a poor texture. 

Churning. — By agitation, it is possible to separate out the fat 
in mass, from the ripened cream, so it can be readily removed 
from the milk serum. As before mentioned the primitive 
churns were undoubtedly made from the skins of animals, and 
the old-fashioned dash churn worked by hand represents another 
simple form. Now churns are run by machinery and may be 
rotating hollow barrels, square boxes or more elaborate forms 
which combine churn and butter worker. The best temperature 
for the rapid gathering of the fat is 65°-7o° F. and under fav- 
orable conditions, butter will appear in from 12 to 30 minutes. 
It can then be easily separated from the butter-milk. 

Washing and Working.— In order to prepare butter for the 
market, it is necessary to subject it to a washing, seasoning and 
working process. The washing with water removes the remain- 
ing butter-milk, but should be carried out with great caution, as 
much of the desirable flavor of butter is soluble in water. Brine 
may be used for wash water or dry salt may next be added, and 
the mass worked into a compact form. The working process 
also separates from, the butter certain non-fatty constituents of 
the cream, which greatly assist in the keeping quality and give 
to the butter a finer texture. Salt is added to give flavor rather 



1 82 FOOD INDUSTRIES 

than for its antiseptic properties. The amount should be small 
or the butter will be unpalatable. Many prefer the taste without 
the addition of salt. The product is called sweet butter and is 
generally considered the highest grade butter on the market. 

Coloring. — The coloring of butter with annatto, saffron or 
coal tar dyes is very largely practiced in the United States. The 
natural coloring of milk varies with the seasons. When cows 
are fed on fresh pasture grasses the butter is a clear bright 
golden yellow, but during the winter months when stall feeding 
is necessary, it develops only a slight yellowish appearance. Since 
the demand is for yellow butter, it has become customary to add 
coloring matter during the working process. Although as a rule, 
it is harmless, the use cannot be recommended. 

Flavor. — The flavor of butter depends largely on the character 
of food given to the cow, to careful methods of manufacture, 
to the amount of salt added, and to sanitary conditions during 
the ripening process and during storage. 

RENOVATED BUTTER. 

A product known as renovated, process or hash butter has of 
late years, been placed upon the market. The material from 
which it is made is gathered from dairies scattered over a wide 
area. Dairy butter made under different conditions will vary 
greatly in color, texture and flavor. When taken to a central 
creamery, these butters are mixed together, melted, purified of 
the rancidity by washing, coloring matter is added and the re- 
sulting mass is rechurned. While the product may be better than 
a poor quality butter, there is danger of more or less rancidity in 
renovated butter. This is caused by the purifying process being 
insufficient, as a prolonged washing would remove the butter-fats 
which are so essential to the flavor of butter. 

OLEOMARGARINE. 

The manufacture of substitutes for normal, dairy butter began 
in 1870 with the experiments of Mege-Mouries, who suggested 
the use of cheaper fats, as a basis for the preparation of a prod- 
uct to be used in the place of butter. These substitutes have 



FOOD INDUSTRIES 183 

been placed on the market under varying names such as oleomar- 
garine, oleo, butterine and lardine, but all are called oleomar- 
garine by the United States Government. 

Oleomargarine has been greatly misrepresented since the early 
days of its manufacture. It has been said to be made from soap 
grease, the carcasses of animals which have died of disease, 
from material extracted from sewage and other unwholesome 
fatty matter. These statements have been far from the truth, 
for oleomargarine is made from pure material, in the cleanest 
possible manner and under the supervision of the Officials of 
the Internal Revenue. When well made it is equally as whole- 
some as butter, and is a very valuable article in the diet of those 
who cannot afford to buy a good quality butter. When sold 
under its own name, it is a product well worth being on the 
market. The chief objection has been the enormous amount of 
fraud practiced. Since the early days of its manufacture, there 
has been a constant disposition on the part of the manufacturer 
and local dealer to sell it as butter and in spite of government 
inspection, this fraud is still largely practiced. 

Materials Used. — The fats utilized as a basis for butter substi- 
tutes are those which have been in the diet of civilized people 
for centuries. Mege-Mouries suggested the use of carefully 
washed beef-suet. Neutral lard, lard stearin, cottonseed oil and 
cottonseed oil stearin are now also largely used. Milk is added 
to give flavor and occasionally egg-yolks to give coloring and a 
firmer, structure. Salt and coloring matter may or may not be 
added. The government requires a tax of ten cents per pound 
for all oleomargarine colored to resemble butter. 

Processes in Manufacture. — Fats are taken from the slaughter- 
house, washed and cooled as quickly as possible to remove animal 
heat. They are cut by machinery into small pieces, heated to 
separate fat from the tissue, cooled, stearin is removed by 
presses and the remaining fat is known as oleo oil. To oleo oil 
a small quantity of neutral lard is added to give body. These 
fats are melted, filtered and churned with milk which has been 
ripened, in a like manner to that employed by butter makers in 
13 



1 84 



FOOD INDUSTRIES 



most creameries. When the churning process is complete, the 
butterine is drawn off into vats filled with ice water which causes 
the fat to solidify into small masses (Fig. 50). The butterine is 
removed by cloth covered screens and deposited on trays, with 
perforated bottoms, where it is allowed to remain until excess 
water has drained off. After the addition of salt, butter is 




Fig. 50.— Chilling Butterine. (Courtesy of Armour & Co., Chicago, 111.) 

worked and finished for the market in a manner similar to the 
processes used in butter-making. 

OLIVE OIL. 

Olive oil was the first of the vegetable oils used by the human 
race, and from the standpoint of the palatability it still holds the 
first place. It has been known from the earliest historic times 
and is supposed to have been introduced into Europe from Asia 
Minor. 

Olive oil is obtained from the fruit of the olive tree where it 



FOOD INDUSTRIES 1 85 

makes up from 40-60 per cent, of the weight of the fruit. The 
oil is found in both pulp and kernel, but the pulp yields the better 
quality. The olive tree grows in semi-arid regions, where rain- 
fall is not abundant and where the temperature is fairly high. 
Spain, Italy, Greece, Southern France and Southern California 
are the principal regions where the olive tree is grown. 

Olives are usually picked when they are three-quarters ripe 
and for the best grade oils are carefully sorted. For these oils 
the choicest olives only are selected and are bruised very slightly 
in a mill. Only the pulp and not the kernel is crushed. The 
crushed pulp is then gathered up and the oil is allowed to drain 
away, without heat and either without or with slight pres- 
sure. This product is known as "Virgin Oil." It has a yellowish 
appearance, a very delicate flavor and has excellent keeping 
properties. Heat and more pressure are applied for a second grade 
oil. For ordinary lower grade olive oil both pulp and stones 
are ground into an oily paste, which is packed into woven grass 
bags and subjected to pressure. The process is continued until 
all the oil has been extracted. The different grades are refined 
by heating to coagulate albuminous matter, which is allowed to 
settle. The lighter colored oils are used for the table, the darker 
for soap-making, lubricating purposes and the like. 

Adulteration. — There has been an enormous amount of adul- 
teration practiced with olive oil on account of the great demand, 
the high price and the ease of substituting other vegetable oils. 
Nearly all of the vegetable oils have the same amber tint as olive 
oil, and when added in certain proportions can scarcely be de- 
tected by taste. Abroad peanut oil has been largely substituted 
for olive oil and in the United States, cottonseed oil has fur- 
nished the chief adulterant. 

COTTONSEED OIL. 

Until comparatively recent years, the cotton plant which is 
cultivated so largely in the Southern States, was used only for 
its fiber. The seed, however, has been found to be particularly 
rich in oil, and rapid development in methods of extraction and 
purification have opened up a new industry, and have placed 



1 86 FOOD INDUSTRIES 

upon the market a comparatively cheap and nutritious edible oil. 
Processes in Manufacture. — The seeds when taken to the mill 
are screened, passed over magnetic iron plates and through ma- 
chines known as linters to remove foreign material such as sand, 
nails and cotton fiber. The short fiber obtained in the linters 
can be used for the preparation of cotton batting. The cleaned 
seeds are hulled, crushed and heated. The cooked meal is en- 
closed in camel's-hair cloth and subjected to hydraulic pressure, 
by which means the oil is removed. Crude cotton seed oil is red- 
dish in color and must be refined. This is accomplished by the 
following processes. After the addition of 10 Be NaOH, the 
oil is heated to 8o°-85° C. and the mass is constantly stirred 
with paddles, until fatty acids are neutralized and impurities pre- 
cipitate out. It is then allowed to remain quiet for many hours 
in a settling tank, after which the "foots" are removed and sold 
to soap manufacturers. The clarified fat is bleached with Ful- 
ler's earth and the color and taste are removed by secret pro- 
cesses. If it is to be sold as salad oil, it is winterized by drop- 
ping the temperature and removing by filtration, any fatty mat- 
ter which has solidified. The oil must stand eight hours at the 
temperature of refrigeration before it is bottled. 

PEANUT OIL. 

Peanut oil is extracted from the peanut by the hydraulic pres- 
sure method, and is refined by processes quite similar to those 
used with olive oil. The first pressing gives an edible oil, used 
extensively in Europe and to a limited extent in the United 
States for salad dressing, either alone or mixed with other oil. 
Subsequent pressing yields a product very frequently employed 
in France for packing cheaper qualities of sardines and other 
food products. Peanut oil is also utilized in the making of fine 
silks as it does not readily turn rancid, and as a lubricant for 
fine machinery because it does not have the tendency to "gum." 
Inferior qualities are used in soap-making and as a basis for 
liniment. The cake which is left after the final pressing is 
highly prized for cattle food, as it contains oil, protein and min- 
eral matter. It may also be utilized as a fertilizer. 



CHAPTER XIV. 



ANIMAL FOODS- 

The animal foods commonly utilized by man in civilized coun- 
tries include the flesh and various organs of cattle, sheep and 
swine, domestic and wild fowl, fish and shellfish, eggs, milk and 
milk products. 

MEAT. 

In the United States, the term meat generally implies the 
edible portion of cattle, sheep or swine. Animals found in the 
wild state, as the deer, moose, bear, squirrel and rabbit, are fre- 
quently highly prized but are used only to a limited extent. 

The Physical Structure and Chemical Constitution.— Whether 
of domestic or wild origin, the muscle of meat is found to 
have a similar structure when viewed through a microscope. It 
appears to consist of tiny fibers which have the form of tubes, 
varying in length in different kinds of meat and in different 
parts of the same animal. The walls of the tubes consist of a 
protein substance which in the living animal is very elastic. It 
is known as elastin or yellow connective tissue. The tubes are 
bound together in bundles by a thin membrane called collagen 
or white connective tissue, a substance of great importance since 
it yields gelatin on boiling. Commercially gelatin may also be 
obtained from the elastin by the addition of an acid, but in the 
household elastin is not materially affected by cooking, except 
that it shows a tendency to harden. 

The texture of meat depends upon the amount of connective 
tissue present, the contents of the tubes and upon the character 
of the walls of the muscle tubes. In a young, well-fed animal, 
the wall of these tubes is a thin delicate membrane and there is 
little connective tissue. The meat is, therefore, tender. The older 
an animal is, however, and the more work it has been required 
to do, the denser becomes the membrane and the larger the 
amount of connective tissue, thus giving a tough texture to the 
meat. 

The value of the meat as food depends largely on the fat and 



155 FOOD INDUSTRIES 

the contents of the muscle tubes, which are chiefly protein. In 
the living animal within the muscle tubes may be found liquid 
myosinogen, paramyosinogen, albumin, alkaline salts and ex- 
tractives. Carbohydrate occurs in the form of glycogen and 
glucose. As glycogen is not stored in large amounts it disap- 
pears very shortly after death. The texture of meat also changes 
considerably at death, caused by the clotting of the principal 
proteins, myosinogen and paramyosinogen. The hardening of 
the muscle tubes known as rigor mortes or the death-stiffening 
causes the meat to become very tough and it should, therefore, 
never be eaten in this stage. Either meat should be consumed 
before stiffening has had time to set in, or it should be hung until 
further changes take place, which again give it a tender texture. 
Rigor mortes is succeeded by the first stages of decomposition, 
during which acids are developed which not only bring about 
important chemical changes, but develop desirable flavors, fresh 
meat being very insipid. The contents of the muscle tubes, 
therefore, differ after hanging. They are found to contain myo- 
sin, metaprotein, extractives, mineral matter and sarco-lactic 
acid. 

Fat. — All meat, however lean it may appear, contains fat. 
Besides that ordinarily visible there is always present more or 
less, occurring in small particles, embedded in the connective tis- 
sue between the muscle fiber. The visible fat varies greatly in 
amount, being comparatively small in veal, chicken and most 
game, while in pork, fattened beef and mutton and in the duck 
and the goose, the amount may reach one quarter to one half of 
the weight of the entire animal. 

Water. — The amount of water contained in meat also differs 
widely, being regulated to a great extent by the fat content as 
other constituents are fairly constant. 

Mineral Matter. — While protein is the chief constituent of 
meat, the mineral matter which it contains, particularly the phos- 
phorus compounds, is also important although it occurs in rela- 
tively small quantities, constituting about 0.3 to 1.9 per cent, of 
the total fresh material. Besides phosphorus, meat contains po- 



FOOD INDUSTRIES 189 

tassium, sulphur, sodium, magnesium, calcium and chlorides. 
Traces of iron are found in lean beef, bacon and ham. 

Meat Inspection. — Since domestic animals are subject to 
diseases which can be transmitted to man, a more or less rigid 
government inspection is now carried on by most civilized coun- 
tries. Chief among these diseases are tuberculosis found prin- 
cipally in cattle and swine, and trachina which occurs exclu- 
sively in swine. 

'Tuberculosis. — Tuberculosis is probably the most frequently 
occurring disease both in this country and abroad. Among cat- 
tle it has probably been the most widespread, occurring not only 
in animals intended for slaughter but among dairy cows, par- 
ticularly those of the Jersey and Guernsey herds. Much ex- 
perimentation has been carried on for many years, to determine 
at what stage meat from animals affected with tuberculosis be- 
comes unfit for human consumption. Experts still disagree on 
this subject. Extremists advise the condensing of the entire 
carcass even though the disease may be in an early stage and 
localized. Most authorities, however, take a more moderate 
view and would allow meat to be sold for food where the disease 
does not exist in a dangerous form, or where it is more or less 
restricted to certain organs. Where the disease has become gen- 
eralized, all agree that the entire carcass should be condemned. 
With modern packing house methods, it has been found that 
even such animals may be utilized for the manufacture of valu- 
able fertilizing material. 

Trachina. — Swine are sometimes found to be infected with 
trachina, a disease resulting from a minute parasitic worm, which 
usually invades the muscular tissues. It was long regarded as 
a harmless parasite, but is now known to cause a disease in the 
human family somewhat similar to typhoid fever. Fortunately 
it is killed when exposed to a temperature of i55°-i6o° F. As 
it is customary in the United States to consume pork well cooked, 
there is practically little danger from this disease. Abroad 
where it is eaten more or less rare, a rigid inspection has been 
found necessary. 



I90 FOOD INDUSTRIES 

Reasons for Cooking Meat. — In great contrast to the carbo- 
hydrate group, protein does not become more digestible on cook- 
ing. In fact, meat fiber subjected to high temperature or pro- 
longed heating becomes toughened and more difficult of diges- 
tion. It is obvious, therefore, that we must look for other rea- 
sons for the almost universal custom of cooking meat. Sterili- 
zation is the reason usually given, but this is only true to a lim- 
ited extent. As meat is not a good conductor of heat, the in- 
terior of large portions, such as roasts, frequently does not reach 
the temperature when all pathogenic bacteria are killed. Neither 
can we hope that harmful ptomaines will be affected if by any 
chance such compounds have been developed. Our real reason 
for cooking is probably the development of desirable flavors, 
largely due to the extractive creatin, which yields creatinin on 
heating. This is important as it is now a well known fact, that 
we do not derive as much benefit from food that we do not 
relish. 

Changes in Cooking. — 1st. The structure of meat is frequently 
changed. Where wet heat or boiling is used, the fibers have a 
tendency to disintegrate. This is caused by the connective tis- 
sue being partially converted into gelatin. 2nd. Certain losses 
always occur in greater or less amount according to the method 
of cooking, temperature and use of r,alt. A loss of water is 
always involved even when the meat is boiled. Part of the fat 
is removed, the amount depending on the temperature and the 
melting point of the fat. Soluble constituents such as albumin, 
mineral salts, extractive and other organic bodies dissolve, es- 
pecially in boiling. To prevent these soluble compounds from 
being lost, some means are taken to coagulate the protein on the 
outside, thus forming a protective coating. This can be accom- 
plished by searing. The use of salt and the question of solu- 
bility are also important. In soup and broth where it is desir- 
able to remove as much of the nutriment as possible, salt should 
always be added, as myosin as well as albumin is soluble in a 
dilute saline solution. Where salt is used to saturation, as in 
pickling or when rubbed on the outside of a roast, myosin is re- 



. FOOD INDUSTRIES I9I 

tained in the meat. Care should be given in pickling that satura- 
tion be kept up. 

The greatest losses in cooking have been found to be in boil- 
ing and roasting, protein, mineral matter and extractives being the 
main constituents lost in boiling, and fat during the process of 
roasting. According to Jordan* the smallest losses occur in pan 
broiling and in sauteing. 

BEEF EXTRACTS. 

The question of solubility plays a very important part in the 
preparation of beef extracts, which may be regarded as soup or 
soup stock prepared from beef. The commercial forms are 
more or less concentrated by the water having been removed in 
vacuo. 

The valuable qualities of such extracts were recognized by 
old time chemists, but they were not known to any great extent 
until after the researches of Liebig. In 1865 a company was formed 
authorized by Ljebig, and a factory was established in South 
America, where cattle could be extensively raised at a lower 
cost than in Europe. The original method of preparation of 
these extracts was very simple. Finely chopped beef was treated 
with eight times its weight of cold water, and the soluble con- 
stituents were extracted by heating under pressure. The extract 
was then filtered, the fat removed to prevent it from becoming 
rancid, and the remaining liquid was concentrated to a paste in 
a vacuum pan. Liebig calculated that it would require thirty- 
four pounds of meat to yield one pound of beef extract, which on 
dilution would make approximately six or seven gallons of beef 
tea. 

When extracts are made according to this method, they con- 
tain besides moisture chiefly mineral compounds 17-25 per cent., 
as potassium phosphate and sodium chloride, and meat bases 
50-60 per cent., as creatin and creatinin. On examination, traces 
of albumin, proteoses and peptone have been found but they are 
not present in large enough quantities to add materially to the 
nutritive value. During the process of manufacture, the major 

* Jordan, Principles of Human Nutrition, p. 317. 



192 FOOD INDUSTRIES 

portion of the beef containing practically all the nutriment is 
rejected. The value of meat extracts must, therefore, depend on 
the mineral matter and the meat bases, or as they are frequently 
termed, the extractives. 

These extractives, of which creatin and creatinin are the most 
important, are nitrogenous compounds but are not able to fur- 
nish the body with constructive material, neither do they yield 
energy. Beef extracts for that reason can scarcely be classed 
as food. Experiments have revealed that animals fed exclusively 
on such material died in practically the same time as those that 
received no food. Notwithstanding the small amount of nutri- 
ment present, beef extracts are valuable on account of their 
flavor and effect on the digestive organs. They are the most 
powerful exciters of the gastric secretion that we possess, and 
are important, therefore, as arousing appetite and as an aid to 
digestion. This is their chief function in sickness and in health. 
They are also of value as flavoring agents. 

Some commercial beef extracts have the addition of protein, 
but the amount is never very great, although advertising matter 
frequently gives customers a false impression as to their nu- 
tritive value. A series of experiments carried on in 1908, at the 
Connecticut Agricultural Experiment Station, showed that "Of 
forty-seven preparations examined, ten only were properly 
branded and up to the standard, seventeen were found to be 
misbranded and varying from the standards, and the others were, 
in general, not up to the standards, though not misbranded." 
The very high cost of these extracts was also reckoned. It was 
found that the dry organic matter present cost from $2.68 to 
$10.18 per pound. The amount far exceeds the cost of home 
made beef extracts which are as a rule far better in quality. 

Beef Juices. — Beef juices may also be found on the market. 
They contain substances of the muscle-fiber which may be ob- 
tained by subjecting finely chopped meat to strong pressure, with 
or without the aid of heat, and concentrating the extracted liquid 
in a vacuum pan. Such products are liable to undergo fermenta- 
tion. They may readily be prepared in the home, by placing 



FOOD INDUSTRIES 193 

finely chopped meat in a jar and surrounding it with water 
heated to 140 F. The juice may then be extracted from the 
meat, by pressure with an ordinary lemon squeezer, and flavored 
with a small quantity of salt. 

INTERNAL ORGANS. 

In the use of internal organs, the custom differs in various 
countries. On the English market, quite frequently are seen 
the heart, the lining of the stomach (tripe), and the kidneys 
particularly those of the sheep. While tripe and kidney may be 
obtained in the United States market, their use is limited and 
the heart is considered of small value. It is disposed of in the 
canning industry or more generally for sausage making. 

Beef tongues are sold largely here and abroad, either smoked 
or in the fresh state. As they constitute a valuable by-product, 
they are handled with great care in order to prevent decomposi- 
tion from setting in and to give the best results in weight and 
appearance. Short tongues are frequently canned, while lambs' 
tongues as a rule are pickled. 

Beef's and sheep's livers are sold in the fresh state and as they 
become stale more quickly than any other edible part of the ani- 
mal, every effort is 1 made to keep them dry and at a low tem- 
perature. They are frequently utilized in the manufacture of 
sausages known as Liberwurst. In the United States, hogs' 
livers are seldom used for edible purposes. They frequently are 
utilized as one of the constituents of dog biscuit or as an in- 
gredient of table sauce. In former years, many were shipped to 
foreign countries where the custom of eating hogs' livers prevails, 
but more stringent laws in regard to methods of preserving such 
material during transportation, has greatly restricted the foreign 
trade. 

Calves' brains and sweetbreads are considered delicacies both at 
home and abroad. In the United States, the thymus gland of 
young animals is placed on the market as sweetbreads. 

FISH. 

From the magnitude of the fish industry, both at home and 
abroad, may be seen the important part that fish and shell-fish 



194 FOOD INDUSTRIES 

play in the diet of the human race. The catch in the United 
States alone reaches approximately 2,200,000,000 pounds annu- 
ally, most of which is consumed in this country, a small propor- 
tion only being prepared in various ways for export. Salting, 
smoking, drying, canning and other methods of preservation, 
have greatly increased the value of fish as a world's product. 
Modern methods of cold storage have also greatly assisted in the 
preservation and transportation of fish. A lower temperature 
than that used with meat has been found necessary, fkh very fre- 
quently being stored in the frozen state. While 32 F. is suf- 
ficient to inhibit the growth of micro-organisms, it will not hin- 
der the action of ferments, which acting upon the tissues, produce 
disagreeable flavors and make the fish unpalatable. Fish which 
has been frozen, however, deteriorates rapidly when thawed and 
decomposition of a very undesirable nature sets in quickly. For 
this reason, fish should be eaten as fresh as possible; it never 
improves on keeping as does meat during the hanging process. 

Fish living in both salt and in fresh water are generally 
edible, being, as far as known at the present time, equally whole- 
some. As a rule those taken from deep, clear and cold water 
especially where the bottom is rocky or sandy are preferable to 
those coming from shallow, warm water or where the bottom is 
muddy. Fish taken from water polluted with sewage are not 
desirable. It is a well known fact that some land-locked fish 
are affected with parasites, at certain seasons, which make them 
undesirable as food. 

Nutritive Value. — The nutritive value of fish is chiefly due to 
the protein and fat content. In protein, fish ranks nearly as 
high as meat, but it is very much poorer in fat, the majority of 
species containing less than 5 per cent. High in fat are the 
herring, lake trout, mackerel and the salmon, ranging from 7.1 
to 17.8 per cent. Many of our common varieties, however, such 
as the bass, bluefish, cod, haddock, perch and the pickerel con- 
tain less than 2 per cent. The small fat content of the greater 
variety of fish is the main difference between meat and fish, when 
compared as to their relative nutritive value. So far as the 



FOOD INDUSTRIES 195 

protein is concerned, fish resembles meat but great differences 
occur in the proportion of fat and water, fish having water 
where meat has fat. Fish contains more gelatin yielding pro- 
teins, but has less extractives. This accounts for the lack of 
flavor and the reason that fish is apt to pall more quickly on the 
appetite. The mineral matter consists chiefly of calcium and 
potassium phosphate and sodium chloride. 

Edible Portion.— Large proportions of fish are inedible and 
must, therefore, be considered as waste matter. This includes 
the skin, scales, bones, head, tail, entrails and fins. The amount 
varies greatly in different varieties, sometimes reaching as high 
as 70 per cent. Taking fish of all kinds, according to Dr. Wiley, 
some 55 to 60 per cent, of the total weight is edible. 

Adulteration. — In the fish market very little adulteration occurs 
except along the line of substitution. Hake and haddock are 
sometimes sold as cod, and inferior salmon for high priced vari- 
eties. This practice of substituting one variety of fish for an- 
other occurs especially along the line of canned goods, as in the 
sardine canning industry, where the herring is frequently used. 

SHELLFISH. 

Chief among the shellfish on our market is the oyster although 
the clam, scallop, lobster, crab, shrimp, turtle and terrapin are 
used at certain seasons, when on account of their cost, they are 
usually considered great delicacies. As regards general com- 
position, they strongly resemble meat and fish except that certain 
of the shellfish, as the scallop and the oyster, contain carbo- 
hydrate in the form of glycogen. 

The oyster has apparently occupied a place in the diet of the 
human race for over 2,000 years. In very remote ages the 
Chinese cultivated artificial oyster beds, and as early as 100 B. C. 
the Italians were engaged in this industry. As civilization ad- 
vanced oyster farming spread to all the maritime countries of 
the Old World and eventually to the Western Hemisphere, 
where it has progressed to such an extent, that the annual crop 
now exceeds the total production of the rest of the world. 

In the United States the oyster is extensively raised on the 



I96 FOOD INDUSTRIES 

Atlantic and Pacific Coasts and in the Gulf of Mexico, especially 
in the vicinity of Louisiana and Texas. Those of the greatest 
value come from Long Island Sound, while the largest crop in 
the world is taken from the Chesapeake Bay. 

Oystermen formerly depended almost entirely on natural. beds 
for their product, but wherever the fishing is active and the de- 
mand great, the natural beds are rapidly becoming exhausted. 
This has led to the cultivation of artificial beds in close proximity 
to public oyster grounds. To promote the oyster industry the 
Federal Government through the Bureau of Fisheries, has co- 
operated with the States "In determining the physical and biologi- 
cal character of the oyster grounds, in surveying and plotting 
those grounds with a view to their allotment for oyster culture, 
in conducting experimental and model operations, in recommend- 
ing oyster legislation and in giving disinterested expert advice on 
the various problems that arise in the development and admin- 
istration of the osyter fishing."* , 

The necessity of guarding oyster beds from sewage pollution 
has been found imperative, through the tracing of typhoid epi- 
demics to the consumption of raw oysters. For a long period a 
custom has prevailed among oystermen of transferring oysters 
from salt to brackish waters, for some forty-eight hours before 
shipping. The rapid absorption of fresh water gives them the 
appearance of fatness, increases their weight from 15 to 20 per- 
cent, and enhances their market value. The practice has proved 
to be unfortunate. Oyster plumping has been frequently carried 
on in estuaries within range of sewers or other sources of con- 
tamination. Where pathogenic bacteria exist in the water, 
oysters are in danger of imbibing disease germs with their food, 
and of acting as carriers of typhoid to the human family. 
Freshening also impairs the keeping quality and alters, the flavor 
through loss of mineral matter by the process of osmosis. 
Chemical tests have further showed that while increasing the 
weight, fattening has deprived the oyster of 10 to 15 per cent, 
of its nutritive value. 

* National Geographic Magazine, March 1913. 



FOOD INDUSTRIES 197 

Deterioration is more rapid after removal from the shell ; 
therefore, while increasing the cost, it is advantageous to ship 
oysters in the shell. They are, nevertheless, frequently shipped 
without the shell after having been washed and placed on ice. 
In this form they can be kept for approximately ten days. 

As regards food value, they are frequently compared to milk, 
as both contain about the same amount of nutritive substances. 
Comparing the relative cost, it may readily be seen that the 
oyster cannot be considered as an economical food. The same 
may be said of the other shellfish, for while all may be classed 
as valuable foods so far as protein and mineral matter are con- 
cerned, their high cost places them among the delicacies rather 
than among our staple products. 

EGGS. 

Chief among the animal fodds used throughout the world are 
eggs. In most countries hens' eggs are used to the largest ex- 
tent although those of other domesticated animals such as ducks, 
geese, turkeys and guinea-hens are frequently found on the 
market. The eggs of birds and reptiles are eaten in certain 
sections of the world, and those of the fish may occasionally be 
found as delicacies, particularly those of the shad and sturgeon, 
the latter being extensively pickled and sold as caviar. 

Physical Structure. — While the eggs of the wild birds vary 
greatly in color, tint, and plain or mottled appearance, those of the 
hen are either brown or white. Through a mistaken idea the 
difference in hens' eggs has greatly affected the market value, 
white eggs selling for a higher price in some localities, while other 
markets give the preference to the brown varieties. Analysis has 
been carried on at the New York State, Michigan and California 
Experiment Stations to determine their relative nutritive value. 
After much experimentation, the conclusion drawn was that 
there is no basis of fact for such popular belief. "Eggs of one 
breed whatever the color of the shells, 'are as nutritious as those 
of another, provided they are of the same size and the fowls are 
equally well fed." 



I98 FOOD INDUSTRIES 

Composition of the Shell. — The shell or protective coating of the 
egg is very largely composed of mineral matter. According to 
Dr. Langworthy 93.7 per cent, is calcium carbonate while mag- 
nesium carbonate and calcium phosphate also appear in small 
amounts. Organic matter is present only to the extent of 4.2 
per cent. 

When viewed through a magnifying glass, the shell is shown 
to be very porous in its nature. This allows the evaporation of 
water and results in the gradual loss in weight of the egg. The 
decrease in specific gravity, therefore, furnishes a very satisfac- 
tory means of judging the freshness of an egg. Brine may be 
prepared by dissolving 2 ounces of salt in 1 pint of water. A 
perfectly fresh egg will sink to the bottom in this solution. Ac- 
cording to the experiments of Siebel, "An egg one day old will 
sink below the surface, but not to the bottom, while over three 
days old will float on the surface, the amount of shell exposed 
increasing with age." 

In marketing eggs, the freshness is usually told by a process 
called "candling." In a dark room, an egg is held between the 
eye and an artificial light; a fresh egg appears unclouded, homo- 
geneous and translucent; a stale egg is cloudy and frequently 
contains dark spots; a rotten egg appears dark colored. A sim- 
ple housewife's test may also be made by shaking an egg held 
near the ear. The contents of the egg should not move. If a 
slight movement can be detected, it is somewhat stale ; if it 
rattles, the egg is spoiled. 

Methods of Preservation. — The porous condition of the shell 
is to a great extent responsible for the rapid deterioration of eggs. 
Bacteria can readily enter and bring about such changes as to 
make the article unfit for human consumption, in a comparatively 
short time. 

In early days eggs were usually marketed near the source of 
supply, but modern times frequently require the transportation 
for long distances. As hens lay more plentifully in the spring 
it is also necessary, in order to secure an even distribution 
throughout the year, to store eggs for use during the fall and 



FOOD INDUSTRIES 199 

winter months. These facts have led to the study of the best 
methods of preservation. Cold storage has been found most 
effective, a temperature near the freezing point being usually 
employed. Eggs thus protected retain their freshness for several 
weeks, but when held for months as is frequently the case, the 
taste and odor are greatly altered. Where decomposition has not 
set in such eggs can be readily used for cooking purposes. 

In order to prevent bacteria from entering, eggs are sometimes 
coated with a non-porous substance. The most efficient of these 
has been found to be a 10 per cent, solution of sodium silicate 
(water-glass). The egg should be carefully wiped with a damp 
cloth, and either coated or placed in a jar containing the water- 
glass as quickly after it has been laid as possible. 

Eggs may also be preserved by the process of drying. Desi- 
cation may be accomplished by spreading the egg in a thin film 
on a dry surface, or by passing the product under pressure 
through drying chambers. Where fresh eggs have been used, 
and where the process of manufacture is such as to make the 
product palatable and care has been given to the storage, such 
a product is wholesome and may be held for a reasonable length 
of time. Dried eggs are used largely by bakers, in camps and 
on long expeditions where fresh eggs are not available. 

Composition of an Egg. — As the contents of an egg were in- 
tended by nature, to furnish the sole nutrition of the young chick 
during the process of development, we might expect to find among 
its constituents, all the elements required for building purposes. 
In this way it bears a strong resemblance to milk, both being a 
perfect food for the animal for which it is intended. Water, 
protein, fat and mineral matter are well represented, while carbo- 
hydrate is present only in a small amount. The nutritive parts 
of the white are chiefly protein, largely in the form of albumins, 
and a small amount of mineral matter. Only traces of fat are 
present. The yolk is rich in fat, protein and mineral matter. 
The fat occurs in the form of an emulsion, held in suspension by 
vitellin, a phosphoprotein resembling the caseinogen of milk. 
Eggs are also rich in sulphur, phosphorus and such elements as 
14 



200 



FOOD INDUSTRIES 



calcium, magnesium, potassium and iron in the form of salts. 
Another important food constituent present in the yolk is lecithin^ 
a compound which furnishes the body with phosphorus in a 
form which can be readily assimilated. The composition of the 
white and yolk, given by Langworthy is as follows : 



Water 

Protein 

Fat 

Carbohydrate 




49-5 
15-7 
33-3 



CHAPTER XV. 



THE PACKING HOUSE. 

Historical. — The packing- industry as it exists to-day was 
founded about thirty years ago, although packing in a very prim- 
itive way, has been practiced since the middle of the 18th cen- 
tury. Starting in the eastern United States, it spread westward 
and in time concentrated in centers near the source of supply 
of the raw material, thus saving the cost of freight on the live 
animal, from the ranch to the market. 

On account of the large grazing areas, it became possible to 
raise cattle in the west in larger numbers than in the more settled 
east, so we find Chicago, Kansas City, St. Louis, Omaha, St. 
Joseph, Fort Worth and other middle west cities rapidly becoming 
important packing house centers. The nearness to the corn belt 
and the water or rail shipping facilities have also played an im- 
portant part in the development of these cities, as centers in the 
packing industry. 

The growth of this business has been very rapid. Although 
of comparatively recent origin, it now ranks fifth in importance 
of the industries of the United States. It is said to be the 
largest and most important industry which is strictly American in 
its conception and development. From the States, it is rapidly 
spreading to most of the new countries of the world. 

Growth and Breadth of the Industry. — Important factors lead- 
ing to the rapid growth of the packing business have been arti- 
ficial refrigeration, concentration and the utilization of by-pro- 
ducts. 

In former times, packing could only be carried on during the 
winter months, as meat cannot be kept in good condition for any 
length of time after slaughtering, unless the temperature is kept 
low. The introduction of artificial refrigeration has now made 
it possible to carry on the business throughout the year. Not 
only has refrigeration become essential in the packing house, but 
its use during transportation has regulated the supply of meat at 
all seasons. 



202 FOOD INDUSTRIES 

Where animals were driven or shipped to the place of consump- 
tion and slaughtered for local demand, the numbers were neces- 
sarily very small and little thought was given to the by-products. 
The fresh beef, the hide, the horns and the tallow were the only 
products used; the remainder was thrown away. This involved 
a great waste of valuable material. When the packing business 
became concentrated, the large amount of waste matter attracted 
attention. This resulted in the conversion of animal products 
that were not fitted for food or for manufacturing purposes, into 
fertilizing material. The fertilizer department once established, 
soon led to the study of the utilization of all by-products. As- 
sisted by Applied Chemistry, means were in time discovered by 
which every available part of the animal could be converted into 
a marketable product. The value of using waste matter which 
formerly had been an expense to .remove is enormous. It has 
been greatly responsible for the rapid growth and development 
of the industry. 

The large modern packing houses consist of many departments, 
where frequently the by-products are elaborated to the finished 
articles, so that they go direct to the consumer from the packer; 
thus we find the high grades of fat being manufactured into 
butterine in one department, lower grades into soap in another 
department. The meat canning industry and the manufacture 
of such products as beef-extracts, pepsin, sausages, gelatin, glue, 
lard, sheep skins, feathers and many articles too numerous to 
mention, are now frequently part of the packing industry. 

Processes in the Packing House. — Inspection and Slaughtering. 
On the arrival of cattle, sheep or swine at the stockyards, an 
inspection is made by a representative of the government and 
where pathogenic conditions are suspected, the animal is seg- 
regated and handled separately. A post-mortem inspection is also 
made on all animals and on all parts of animals, to be utilized as 
food (Fig. 51). 

As a rule, animals found to be healthy are not slaughtered until 
the day after their arrival at the packing house, thus avoiding 
any abnormal conditions such as over excitement and fatigue. 



FOOD INDUSTRIES 203 

After slaughtering they are bled and the hide, head, feet and 
internal organs are removed. They are then scrubbed and 
washed in each part, after which they are removed to the cooler, 
where they hang until ready for shipment or until they are sent 
to the cutting room for curing, sausage making or canning. 

Beef are hung far enough apart to admit free circulation of 
air and the temperature is dropped as quickly as possible to 




Fig. 51.— Beef Viscera Inspection. (Courtesy of Armour & Co., Chicago, 111.) 

40°-45° F. where it is maintained for twelve hours, after which 
it is gradually dropped to 34°-35° F. The temperature is seldom 
allowed to fall to the freezing point. 

Hides, Pelts and Bristles. — As the hide of beef constitutes the 
most valuable by-product, great care is given to the handling 
and curing, preparatory to delivery to the tanner. It is removed 



204 FOOD INDUSTRIES 

from the freshly killed animals, by skilful workmen, freed from 
adhering flesh and fat and quickly cooled. A combination of 
fine salt and rock salt which has been crushed and screened, is 
spread over each hide and they are piled one above the other. 
During the curing process, which lasts for 25-30 days, more or 
less of shrinkage takes place, after which the salt is removed and 
they are prepared for shipment. 

The pelts of sheep are also removed after slaughter. When 
not disposed of while fresh, they are cured by salting and some- 
times treated so that the wool can be easily removed from the 
skin. 

After the slaughter and scalding of swine, the bristles are taken 
from the back and ham and are cured first by drying, either in 
the sun or with artificial heat and then by salting They are used 
for the manufacture of brushes or made into curled hair for 
stuffing mattresses, cushions and similar articles. At the present 
time, the best bristles are being obtained from Russia and China. 

Fat. — The second important by-product is fat, which is ex- 
tensively used for the manufacture of edible products and many 
useful articles. From the bullock, three grades of fat are ob- 
tained. The 'first grade yields oleo stock from which, by further 
treatment, oleo oil and oleo stearin are obtained. The latter prod- 
uct is largely used in the preparation of compound lard. Oleo 
stock is frequently called butter-fat as oleo oil is one of the chief 
constituents of butterine. Oleo oil may be sent to a separate de- 
partment of the packing house to be made into artificial butter, 
or as raw material, it may be sold to the manufacturer of butter- 
ine. For this purpose, large quantities are shipped abroad, the 
greater part going to Holland from which place it is distributed 
to other European countries. 

A high grade of fat may also be rendered for edible tallow. 
This was the type fat used originally in the manufacture of oleo- 
margarine. For the manufacture of artificial butter see Chapter 
XIII. A second grade of fat is rendered for ordinary tallow 
which may be further separated into tallow oil and tallow stearin. 
Several grades of tallow are known. They may be used in soap 



FOOD INDUSTRIES 



205 



making, candle manufacture and in the preparation of glycerine, 
oleic and stearic acids. Tallow may be utilized for lubricating 
purposes, being generally compounded with other material. 

From the sheep, tallow may also be obtained. It is hard and 
white in appearance and is known as mutton tallow. 

One of the most important factors in the packing house is the 
rendering of the fat from hogs. Several grades, prepared by 




Fig. 52.— I^ard Boiling. (Courtesy of Armour & Co., Chicago, 111.) 

different processes, are placed upon the market, known as kettle 
rendered lard, prime steam lard, refined lard and compound lard. 
The last named product is a substitute for lard and consists 
largely of cotton seed oil, oleo stearin and tallow. Kettle rendered 
lard is the highest grade of household lard. It is generally sup- 
posed to be made entirely from leaf lard, but only two-thirds 
leaf lard is used as a rule, the remaining amount being fat taken 
from the back. Neutral lard is made principally from leaf lard 
but by a more complex process (Fig. 52). 



206 FOOD INDUSTRIES 

The Feet. — From the feet of salughtered animals, a valuable 
oil known as neats-foot oil may be obtained. The bones are 
sawed, separated from the hoofs, washed to free them from 
blood and subjected to live steam. During this process, the bones 
fall apart and the oil separates out. The bones may be ground 
into meal and the liquid containing dissolved protein may be 
utilized for the manufacture of glue. The oil which is drawn 
off is refined and used largely for leather dressing. 

Bone Products. — From the bones of the head and feet many 
useful products may be obtained. One of the most valuable is 
bone-black, which is largely used in the industries for decoloriz- 
ing, as in the bleaching of sugar, glucose and similar products. 
A black pigment may be secured also, and used as a pigment for 
paints and shoe blackings. Some bones are ground and used for 
fertilizing purposes while others are worked up into fancy articles 
such as knife handles, buttons, combs, fans and many similar 
products. 

Tankage. — Tankage is the name given to the residue which 
remains in the tanks where meat scraps have been rendered to 
separate out the fat. In former years, it was always considered 
waste material and was thrown away. The operation consists 
in boiling down the meat scraps, under pressure in a closed tank 
or "digester," for several hours. After all the parts are thor- 
oughly disintegrated from the effect of the high temperature, 
the fatty matter separates out and can be withdrawn through 
outlet pipes and by the process of skimming. The material which 
remains in the vats is passed through filter cloth and pressed, 
until most of the water and any remaining fat are removed. It 
is then dried, screened, and used as fertilizer base. The com- 
mercial value depends on the amount of ammonia and bone- 
phosphate which it contains. As the tank water is very rich in 
material which contains ammonia, it is concentrated to a syrupy 
consistency in a vacuum pan, mixed with copperas and dried. 
It is known as "concentrated tankage" and is used for mixing 
with low grade tankage to increase the percentage of ammonia. 

Blood. — The blood which flows from the slaughtered animals 



FOOD INDUSTRIES 20"J 

is conducted through drains to large vats or receptacles, care 
being given to keep it free from all foreign matter, such as 
refuse, manure and water. It is then cooked by live steam until 
the albumin has coagulated, after which it is pressed and dried. 
Dried albumin may be ground and screened if desired. Albumin 
is used extensively as a fertilizer and in the textile industry in 
setting the color permanently in such material as gingham. The 
drained blood is sometimes used in beet sugar refining as a clari- 
fying agent ; it is then known as "sugar house albumin." 

Mixing Fertilisers. — To make a complete fertilizer, phosphoric 
acid, ammonia and potash must all be present. As only ammonia 
and phosphorus compounds are obtained from bones, tankage 
and blood, it is necessary to add a potassium salt, such as potas- 
sium chloride or sulphate. According to need, they are mixed 
in different proportions, and are thoroughly incorporated with a 
filler as earth or ashes which acts as a diluent, the fertilizer 
when used alone being too strong for plant life. 

Glue and Gelatin. — Glue and gelatin can be made from many 
by-products of the packing industry. The chief sources are the 
liquids in which have been boiled cattle and sheep's heads, feet, 
bones, sinews, hide trimmings, calves' heads and pigs' feet. Many 
grades may be obtained from fine white gelatin to a low grade 
dark appearing glue, according to the part of the animal used, 
the condition of the raw material and the care in manufacture. 
In order to produce a high grade product, careful attention must 
be given to the raw material in order that decomposition does 
not set in. Only that which is in a sound, sweet condition should 
be utilized. It is also essential that a low temperature be used 
in concentrating the glue liquor, so that scorching may be pre- 
vented and undesirable changes may not take place. This is 
accomplished by evaporating the liquid, to the desired density, 
in a vacuum pan from which it is run into molds, chilled and 
clarified. It is then cut into layers and dried in an oven. 

In order to dissolve the mineral matter, bones are frequently 
leached with an acid. By allowing them to remain in dilute 
hydrochloric (2° Be.) or phosphoric (6° Be.) for three or four 



208 FOOD INDUSTRIES 

weeks, the bones become soft and spongy. They are then freed 
from the acid by careful washing, after which- they are converted 
into gelatin. 

Bleaching the bones before cooking the glue liquid is practiced 
by many manufacturers. Sulphur dioxide is most frequently 
used, although other bleaching agents may be employed, such as 
zinc sulphate or chloride and peroxide of hydrogen. In addition 
to bleaching these agents act as preservatives, thus preventing 
decomposition from setting in. Formaldehyde is also used in 
small quantities as a preservative. 

Canning of Meat, Beef Extracts, Sausages, etc. — As a rule 
the canning of meat is carried on as a separate industry. See 
Chapter XIX. It is, however, one of the side issues that is fre- 
quently found in the packing house, being established with the 
view of saving a large proportion of meat that would otherwise 
be wasted, or would be sold at a very low price. In this way 
many of the cheaper cuts of meat, which are nourishing and 
healthy, can be utilized. The preservation of meat by hermet- 
ically sealing, has led to still another department within the 
packing house. In the soaking and cooking of meat, part of the 
water-soluble constituents are dissolved out. By concentration 
in a vacuum pan, these waste liquors together with the bone 
liquid, may be converted into beef extracts. Fresh meat is 
rarely used for this purpose among packers, consequently the 
cost of preparing beef extracts by them is very small. For 
manufacturing processes, see Chapter XIV. 

In the sausage department, the packer finds another way of 
disposing of those portions of meat which are nutritious but not 
palatable in their original condition. Sausages, bologna, frank- 
furts, scrapple and similar products are prepared after various 
formulae and placed upon the market. Besides meat from differ- 
ent parts of the beef and pork, such products may contain corn 
flour, cracker meal, boiled potatoes, starches and dextrins. These 
are frequently spoken of as "fillers" and serve to prevent shrink- 
age in bulk under the influence of heat. A great variety of 
flavoring agents are added, such as sugar, salt, white or red 



FOOD INDUSTRIES 209 

pepper, cinnamon, mace, allspice, cloves, coriander, carraway 
seeds, marjoram and onions or garlic. Salt-petre and color 
water, consisting of dyes of various kinds, assist in giving a 
better appearance. A common practice still exists in the use of 
borax and boracic acid for purposes of preservation. 

The manufacture of animal casings from the round or small 
guts, middle or large intestines and bladders, of cattle, sheep 
and hogs, furnish another example of the utilization of material 
entirely lost until the establishment, of the modern packing house. 
In order to supply the demand, artificial casings may be pre- 
pared from cellulose, to take the place of animal casings. To 
improve the appearance of casings, to insure against shrinkage 
and to prevent molding, varnish is sometimes used. It is pre- 
pared from shellac, boracic acid, ammonia and water. 

There is probably more chance for deception in the manufac- 
ture of these products than in any other form of animal food 
found on the market. When properly prepared, they are highly 
prized as food products. The frequent use, however, of such 
material as borax, boracic acid, sulphite of soda, undesirable 
colorings and excessive quantities of filler, is making the inspec- 
tion of factories the only safeguard that the consumer has for 
protection against the adulteration of these products. 

Minor Packing House Products. — In connection with the pack- 
ing industry, many other branches may be found, such as the 
manufacture of chipped dried beef, the curing and smoking of 
tongues and hams, and the preparation of pharmaceutical prod- 
ucts from the various organs of slaughtered animals. From the 
mucous membrane of the stomach of hogs, pepsin is made and 
a similar ferment known as pancreatin may be obtained from 
the pancreas or sweetbreads of animals. 

In a like manner, from the bullock may be extracted cardine 
from the heart, medulline from the spinal cord, musculine from 
the muscular tissues and cerebrine from the brain. The thyroid 
glands of the sheep and the bullock yield thyroidine. It is 
claimed that these extracts from animals are beneficial in the 
treatment of diseases of human organs similar to those from 
which the extracts are prepared. 



CHAPTER XVI. 



MILK. 




Fig- 53- — Burnside Kaira, N. Y. 

Source. — Milk is a white opaque fluid which is secreted by the 
lacteal glands of the female of all animals, which belong to the 
mammalian class. It is intended by nature to supply nourish- 
ment to the young, until such a time as it is able to take food 
similar to that utilized by the parents. 

In different parts of the world various animals are bred for 
the purpose of producing milk for the use of mankind. Prob- 
ably the goat was one of the first animals to supply milk to the 
human family, and in the rough, hilly districts of Europe, espe- 
cially in the Swiss Alps, it is still very common. The milk of the 
buffalo, the camel, the mare and the reindeer is frequently used, 
while in parts of Europe the ewe has produced much milk for the 
manufacture of cheese. 

History does not tells us how the cow came to be developed 
as a producer of milk, but in most civilized countries where the 
climatic conditions permit, cow's milk is almost entirely used. 
It is not more desirable for human food than the milk of other 
animals, but in her development the cow has shown herself to 



FOOD INDUSTRIES 211 

be able to give the best return for a given amount of care and 
feeding. 

Composition. — Chemically milk is composed of all the essentials 
necessary to sustain life for a long period and is, therefore, fre- 
quently spoken of as a perfect food. It can only be regarded in 
this light, however, when utilized by the type of animal for 
which it is intended. 

The composition varies in different animals, even in animals 
of the same species, but the difference is rather in the relative 
proportion of the various constituents, than in the general prop- 
erties and composition of the ingredients themselves. The fol- 
lowing figures will give a general idea of the composition of 
cow's milk, although a great variation may occur according to 
the breed, age of cow, period of lactation, amount and character 
of the food, etc. 

Per cent. 

Water 87.2 

Total Solids 12.8 

Fat 3.6 

Carbohydrate 4.9 

Protein 3.3 

Mineral matter 0.7 

Water is the largest constituent of the milk, containing in solu- 
tion, semi-solution or in suspension, the remaining ingredients 
which are known as the total solids. Of these total solids, fat is 
commercially the most important as it is the source of butter 
and to a great extent cheese. The amount differs more than any 
other constituent, being low in the Holstein and relatively high 
in the Jersey and Guernsey. The average should not fall below 
3 per cent, and except in very rich milk, it will not exceed 5 per 
cent. 

Fat occurs in milk as an emulsion, suspended in the milk 
serum in the form of globules. On account of their specific 
gravity these globules rise more or less readily to the top, when 
milk is allowed to remain at rest, and are then known as cream 
or top milk. 

Chemically, the fat which is known as butter-fat exists in two 



212 FOOD INDUSTRIES 

forms, non-volatile and volatile. The non-volatile or insoluble 
fats make up about 90 per cent, of the total amount, and consisx 
of a number of fats of which palmitin, olein and stearin are the 
most important. The characteristic taste and odor of milk and 
butter are largely due to the existence of certain volatile fats, 
butyrin, caprin, caproin and caprilin which constitute the re- 
maining 10 per cent. Of these butyrin is the most important. 
It occurs in the largest proportion and is the fat which on de- 
composing yields butyric acid, readily detected in rancid butter. 

The carbohydrate in milk is known as lactose or milk sugar. 
It belongs to the disaccharid group as do sucrose and maltose, 
and is similar so far as its ultimate composition is concerned. 
The most marked difference is solubility; sucrose and maltose 
are very readily soluble in water while lactose dissolves with 
difficulty. Milk sugar, therefore, does not possess the sweeten- 
ing power of the other disaccharids and is not apt to pall upon 
the taste so rapidly. 

Lactose does not readily yield to yeast fermentation, but under 
the influence of certain bacteria found in all normal milk, it 
undergoes partial decomposition yielding lactic acid according 
to the following formulae : 

C ]2 H 22 O n , H 2 — 4CH3 CHOH COOH. 

This change begins in the milk as a rule almost immediately 
after it is drawn from the cow and continues until 0.9 of 1 per 
cent, is formed, when further decomposition is checked by the 
lactic acid. 

The chief protein of milk is caseinogen which exists in an 
extremely fine colloidal state in intimate contact with calcium 
phosphate. Caseinogen will not coagulate on heating, but when 
subjected to an acid which combines readily with the calcium, 
it will precipitate out of the solution in the form of a curd. It 
is very important commercially as it is one of the chief constit- 
uents of cheese. Albumin and globulin also occur in solution in 
milk but in relatively small amounts, approximately 0.5 of 1 
per cent, of the total protein. They are essentially the same in 



FOOD INDUSTRIES 213 

chemical composition as the albumin and globulin found in blood 
and egg. 

Mineral matter is present in a relatively large amount, 0.7 of 
1 per cent, in cow's milk and is utilized mainly for building pur- 
poses. Small amounts of a variety of salts occur — phosphate 
of lime and potash, chlorides and sulphates of sodium and potas- 
sium, with very small amounts of iron and magnesium. Human 
milk contains much less inorganic matter, approximately 0.2 
per cent, being present. It is frequently necessary, therefore, in 
infant feeding to modify milk so it will more closely resemble 
mother's milk. 

Milk contains several other constituents occurring in minute 
quantities. Lime occurs in combination with citric acid in the 
form of a salt known as citrate of lime. It is also rich in various 
enzymes which assist in the digestion of the protein, fat and milk 
sugar. For a short period after it has been drawn, bactericidal 
bodies are present. The characteristic color of the fluid is 
largely due to lactochrome, which occurs in varying amounts, 
and is generally supposed to be intimately associated with the 
palmitin. 

IMPORTANCE OF THE MILK SUPPLY. 

Of all our standard articles of food none have received as 
much attention as the production and handling of milk. The 
reason for this may readily be seen, for it has been found that 
milk is more apt to be dangerous to health than any common 
food product. It deteriorates very rapidly and as it is usually 
taken in the raw state, no protection is afforded the consumer 
through the process of cooking. The fact that it forms the sole 
diet of the human being at an immature age makes this problem 
a very serious one. Should there be any contamination, the 
child would be liable to take it when least able to cope with a 
disease. 

Besides the chemical compounds previously considered, milk 
contains a large number of bacteria which gain access to it after 
it is secreted. Unfortunately the warmth of the milk, its fluid 
condition and its composition make it a most favorable medium 



BacterialTests 

OF 

Creamery Milk 



i 



FARMER'S MILK 

DELIVERED 
TO CREAMERY 



SAME MILK AFTER 
PASTEURIZING lMIN. 
AT 155' F. 



SAME MILK ArTER 

5 MINUTES IN 
CREAMERY Mil K CANS 



WATER IN WHICH 
MILK CANS RECEIVE 
TINAL RINSING 



o 

MILK FROM SAME 
CANS AFTER ARRIVAL 
IN NEW YORK CITY 
NEXT MORNING 






5,000,000 

B/*CTERIA 
PER CC 



6700 

BACTERIA 
PER CC 



560.000 

BACTERIA 
PER CC 



1.270.000 

BACTERIA 
PER CC 



90.000.000 

BACTERIA 
PER CUBIC 
CENTIMETER 



Careless Handling 



NY MILK COMMITTEE 



Bacteria Counts Tell the Story of Unsanitary Conditions 

Fig. 54- 



BacterialTests 

OF 

Creamery Miek 



i 



I 



FARMER'S MILK 
DELIVERED 
TO CREAMERY 



SAME MILK AFTER 
PASTEURIZING 30 MIN. 
AT U5* F 



SAME MILK AFTER 

3 MINUTES IN 

CREAMERY BOTTLES I 



WATER IN WHICH 

BOTTLES RECEIVE 

FINAL RINSING 



MILK FROM SAME 
BOTTLES AFTER 
ARRIVAL IN NY.CITY 
NEXT MORNING 



28,000 

BACTERIA 
PER C.C. 



3,000 

BACTERIA 
PER C.C. 



3,000 

BACTERIA 
PER C.C. 



NO 
BACTERIA 



5,000 

BACTERIA 

PER CUBIC 

CENTIMETER 



Careful Handling 



NY.MILK COMMITTEE 



Bacteria Counts Tell the Story of Sanitary Conditions 

Fig- 55- 



IS 



2l6 FOOD INDUSTRIES 

for the growth of these micro-organisms. They reproduce very 
rapidly and unless precautions are taken to inhibit their increase, 
the number becomes enormously large in a comparatively short 
time (Figs. 54-55). Through their action, changes begin to 
take place in the milk constituents and in time decomposition 
advances so far, that the milk is no longer fit for consumption. 

Diseases from Milk.- — The greater number of the germs in milk 
are harmless excepting the germs of' specific diseases as tuber- 
culosis, typhoid, scarlet fever, diphtheria and septic sore throat. 
The most dreaded disease is that of tuberculosis. The bacilli 
may come directly from the cow affected with bovine tuber- 
culosis, in which case there is a possibility of large numbers be- 
ing present in the milk when it is drawn from the teats. Such 
milk when mixed with that drawn from other cows, may con- 
taminate the supply from the entire herd. Expert examination 
has proved that the disease is as prevalent among cows as it is 
in the human family especially when the animal has been kept 
under bad hygienic conditions. Rosenau states* "The fact that 
bovine tuberculosis is frequently fatal, especially in children, 
may be divined from the fact that fifteen per cent, of the fatal 
cases of tuberculosis in children under five year of age that have 
been studied, were due to the bovine type of bacillus" and "from 
five to seven per cent, of all human tuberculosis is ascribed to 
infection with the bovine bacillus." This shows the importance 
of the care which should be given in the milch cow and the 
necessity of making the tuberculin test from time to time. 

Milk may also be contaminated from persons having pulmonary 
tuberculosis or through the contaminated cloths or insanitary 
actions of the milker. It is believed that epidemics of diphtheria 
and scarlet fever have been caused by the milk supply, probably 
through secondary infection. The great importance of the 
health and cleanliness of the milker and his family is again 
shown in typhoid, since the cow does not have that disease. An 
impure water supply in which milking utensils are washed has 
frequently been the cause of the spread of typhoid. For this 

* Rosenau — The Milk Question, p. 100. 



FOOD INDUSTRIES 2.1J 

reason no water which is not above suspicion should be used 
about the dairy, for either drinking or washing purposes. In 
recent years, pathogenic streptococci causing sore throat have 
been traced to infected milk. 

Cholera infantum is believed by some authorities to be due to 
the abnormal increase of bacteria of filth, rather than to any one 
species of micro-organism. That it is due to milk bacteria has 
been proved by the fact that the trouble occurs in greatest 
abundance at the season of the year when milk bacteria are most 
numerous ; that it is chiefly confined to infants fed upon cow's 
milk and that the disease is greatly reduced when care is given 
to supply pure milk. 

Necessity for Cleanliness. — Since milk may so easily become 
contaminated, since it is a favorite medium for the development 
of bacteria and must so frequently be carried a long distance, 
cleanliness is an absolute necessity in the production and handling 
of our milk supply. Means should also be taken to prevent 
the growth of micro-organisms, for even when produced under 
sanitary conditions, bacteria in small numbers are always present. 
Their development may be inhibited by dropping the tempera- 
ture immediately after milking to 50 F. and maintaining this 
temperature until the milk is delivered. The importance of per- 
fect cleanliness and low temperature cannot be over-estimated. 

Safeguarding the Milk Supply .—To safeguard the supply, laws 
have been passed by the city and state governments, which while 
differing in detail, contain the same general rules. As regards 
composition milk must not contain more than 87-88 per cent, 
water and should contain 12-13 P er cent- total solids of which 
3 per cent, should be fat. It must be guarded from producer to 
consumer, by surrounding it with sanitary conditions and a tem- 
perature sufficiently low to prevent growth of micro-organisms. 
No preservative, such as borax, boracic acid, salicylic acid or 
formaldehyde should be used. Some cities also have a law in 
regard to the bacterial count, but this has been found imprac- 
ticable in large communities. 

Because of its wide usage as a food, milk is more closely 



2l8 FOOD INDUSTRIES 

supervised than other articles in the diet. It is inspected at the 
farm, at creameries, during transportation, at receiving stations 
and in distributing centers. Regulations are now more or less 
enforced affecting surroundings where milk is produced. The 
water supply must be above suspicion. The utensils should be 
heavily tinned and seamless. They should be subjected each day 
to a thorough washing and if possible to live steam or exposure 
to sunlight. The stables should be light, well ventilated and fre- 
quently whitewashed. No utensils, feed or other animals should 
be kept in the stables. Bedding and manure must be. daily 
removed. The cow should be healthy and kept as clean as pos- 
sible. The milker and dairyman's family should be free from 
contagious disease. The milk should be drawn through a small 
mouthed sanitary milk pail, strained and cooled immediately. 

During the journey to the consumer milk should be kept out 
of contact with air and should be iced. Sanitary conditions 
should also prevail where it is distributed. Although the state 
may control more or less the supply of milk from the producer 
to the consumer, once in the hands of the housekeeper, the law 
is powerless to control the handling of milk. Too frequently 
through ignorance or utter carelessness, milk which has been 
carefully handled by farmer and distributor is ruined by the 
housewife. It is as much her duty to see that milk is guarded 
carefully as it is of those who have handled it before her. The 
following hints to housekeepers have been contributed by some 
of the students of Teachers College: Buy for daily use; buy 
bottled milk whenever possible; when milk must be bought from 
an open can, use a covered receptacle to put it in, as a glass fruit 
jar; do not transfer bottled milk to another receptacle; on receiv- 
ing, wash the top and outside of the bottle thoroughly and place 
at once near the ice in the ice-box ; do not mix old. and new milk ; 
since milk absorbs odors, do not put strong smelling food near 
it ; keep well covered at all times ; when the bottle is empty, rinse 
with cold water, wash thoroughly with hot water and set to drain 
away from dust; do not use milk bottles for any other purpose; 
if there is a contagious disease in the family, until the danger is 



FOOD INDUSTRIES 2IO, 

over, place a clean covered container where the milkman may 
pour the contents of the milk bottle which he is delivering into 
the container, or keep all bottles delivered during the period of 
illness before returning, at which time they should be thoroughly 
sterilized; general rule- — keep milk cold and free from dirt. 

Our Duty to the Producer. — As the study of the milk problem 
advances, more and more has been required of the producer. 
The law now demands that cows must be in a healthy condition, 
that old barns and surroundings must be cleaned or new barns 
built, stables must be whitewashed, the water supply must be 
examined, new utensils must be bought and more care must be 
given to cleanliness, which means more labor at an additional 
cost. These requirements have greatly added to the cost of the 
production of milk, and the farmer can no longer supply milk 
at a profit for the same price as when insanitary conditions pre- 
vailed. The advance in price should, therefore, be cheerfully 
borne by the consumer who is receiving a far better product 
to-day than in years gone by. 

Testing of Milk. — Milk is usually tested by the lactometer 
which registers the specific gravity, and by the Babcock test which 
gives the percentage of fat and also assists in the detection of 
formaldehyde. The estimate of the amount of water and total 
solids is made together with the bacterial count. For further 
information in regard to these tests see a standard work on milk 
as Milk and Its Products by Wing, The Production and Handling 
of Clean Milk by Winslow, Harrington's Practical Hygiene, or 
Van Slyke's Methods of Testing Milk and Milk Products. 

Sterilization. — Even with ordinary care milk contains a large 
number of bacteria which multiply rapidly. As previously seen 
they may be a harmless type or those of specific diseases. These 
troubles have led to the treatment of milk by heat, the oldest 
method being that of sterilization. 

As sterilization means the destruction of all micro-organisms, 
it is necessary either to hold milk - at a temperature of 248 ° F. for 
15 minutes or to raise it to the boiling temperature on three suc- 
cessive days. This insures not only the destruction of bacteria 



220 



FOOD INDUSTRIES 




A B c 

Fig. 56. — Pasteurization of Milk. The milk passes from the receiving tank (A) through 
the clarifiers (B) to the pasteurizer (C) where it is heated to 145 F. It is then con- 
ducted to the holding tanks (Fig. 57). (Courtesy of the Sheffield-Farms-Slawson- 
Decker Co.) 




Fig. 57. — Holding Tanks. Milk heated to 145 F. is conducted successively to four 
holding tanks where it is held for fifteen minutes in each tank. At a temperature 
of about 142 F. it passes back through the pasteurizers and is rapidly cooled. 
(Courtesy of the Shefneld-Farms-Slawson-Decker Co.) 



FOOD INDUSTRIES 



221 




Fig. 58.— Milk Coolers. (Courtesy of the Sheffield-Farms-Slawson-Decker Co. 




Fig- 59.— Milk Bottling Machine. (Courtesy of the Sheffield-Farms-Slawson-Decker Co.) 



222 FOOD INDUSTRIES 

but spores of a highly resistant type and renders the milk practi- 
cally sterile. If air be excluded such milk can be held indefi- 
nitely. While undoubtedly this is the most effective method of 
protecting milk against bacterial decomposition, it unfortunately 
so alters the composition as to make it more difficult to digest. 
This has proved so serious an objection that sterilization has 
been practically abandoned in America, and either pasteuriza- 
tion or the use of clean raw milk has taken its place. 

Pasteurization. — The term pasteurization means the heating of 
milk below the boiling point, from 140 to 160 F., followed by 
rapid cooling (Figs. 56-59). This method was named from Pasteur 
who suggested its use in 1864 for the preservation of beer and 
wine. It was not, however, until 1886 that the process was ap- 
plied to milk. It differs from sterilization mainly in the degree 
of heat to which bacteria are subjected. All micro-organisms 
are not destroyed by this method so pasteurized milk will in time 
decompose. It has been found, nevertheless, that from 95 to 98 
per cent, of bacterial life and practically all of disease bacteria 
have been rendered harmless, so milk thus treated can be kept 
from souring from twelve to twenty-four hours longer. If milk 
has been kept for a period before pasteurization, poisons may 
have been formed in it which heat will not destroy. It is, there- 
fore, absolutely essential that only clean, fresh milk should be 
pasteurized. The process can in no way take the place of 
cleanliness and should never be used to atone for insanitary 
methods in the production and handling of the milk supply. 

If a low temperature has been used pasteurizing does not 
injure milk so far as its nutritive value is concerned and it af- 
fords a certain protection against such diseases as tuberculosis 
and typhoid which have been previously discussed. 

Certified Milk. — The term is intended to signify that the milk 
is certified as to its quality and wholesomeness by a medical 
milk commission. While pasteurization properly carried out has 
greatly assisted in safeguarding the milk supply of large cities, 
where enormous quantities must frequently be carried long dis- 
tances, it is by no means ideal. It frequently means a purified 



FOOD INDUSTRIES 223 

rather than a pure milk. This has proved satisfactory for or- 
dinary household purposes and for adults, but in infant feeding 
nothing can take the place of pure raw milk produced under 
ideal conditions. A standard of excellence has been fixed by 
medical commissions and milk which can satisfy these require- 
ments is sold under the name of certified or guaranteed milk. 
The bacterial count must be low, and it must possess the other 
characteristics of pure wholesome milk. This can only be se- 
cured by perfect cleanliness in regard to the dairy, dairy methods, 
care of the cow, and health of the milker. To comply with 
sanitary regulations means an excess cost to the producer, so 
certified milk may be sold at a higher price. Such milk is fre- 
quently sold under the special name of the dairy, as Walker- 
Gordon milk. 

Modified Milk.- — As the composition of cow's milk differs from 
that of human milk, being higher in protein and mineral matter 
and lower in milk sugar, it is frequently found necessary to 
change the composition of cow's milk to more nearly make it 
resemble that of the human being, or to give a milk of known 
composition especially adopted to the particular needs of the 
infant or invalid. Water, barley water, lime water or dextrin- 
ized gruel may be used as a diluent and cream and milk sugar 
may or may not be added. Such a product is called modified 
milk. 

All precautions stated above for the production and handling 
of clean milk as well as the requirements of the certifying 
Medical Society should be observed in producing modified milk. 



CHAPTER XVII. 



MILK PRODUCTS. 

Condensed Milk. — The importance of milk in the diet and its 
rapid deterioration even under the most favorable conditions, 
have led to much experimentation along the line of its preserva- 
tion for a long period. 

In the early part of the 19th century, an attempt was made 
to hold milk indefinitely by reducing the percentage of water. 
As a high temperature was used in the condensing process, 
the result was a boiled milk, the composition of which greatly 
differed from the raw material. Lactose like any other sugar 
caramelized in time and gave to the finished product a dark 
color and a bitter tatse. Lime salts, so necessary in the digestion 
of milk, were thrown out of solution and the protein matter was 
much altered in composition. The process proved a failure. 

It was not until 1856 that another attempt was made to pre- 
serve milk by condensing it. At that time Gail Borden was 
granted a patent "On a process for concentrating milk by evapo- 
ration in vacuo, having no sugar or other foreign matter mixed 
with it." This early process reduced the temperature to 160 F. 
and eventually resulted in placing a satisfactory product on the 
market. Although the early days of the condensed milk business 
were full of discouragement to the manufacturer, the industry 
has now grown to enormous proportion, rapid strides having 
been made during the past ten years. This shows the rapid 
increase in the consumption of condensed milk not only in coun- 
tries where the breeding of the cow is impossible, but also for 
use on ocean liners, in the navy, lumber and mining camps and 
in home markets. 

The successful condensing of milk requires that the raw 
material be produced under the best hygienic surroundings, and 
invariably the dairy conditions will be found to be in a high 
state of development, wherever milk is being produced for the 
condensing industry. 



FOOD INDUSTRIES 



225 




226 FOOD INDUSTRIES 

There are two classes of condensed milk, sweetened and 
unsweetened. 

Process. — When milk is received at the factory it is tested, 
filtered to remove dirt, and immediately sterilized by raising the 
temperature of the milk to the boiling point. Sugar is added to 
the extent of about 16 pounds to ioo pounds of milk. The 
sweetened fluid is run into a vacuum pan and kept at a tempera- 
ture of approximately 130 F. until it is condensed about two 
and one-half times. When sufficiently concentrated it is run into 
40 quart cans which are surrounded by ice. During this opera- 
tion which lasts one hour, the milk is constantly stirred with 
paddles after which it is immediately run into tin cans, capped, 
labeled and boxed. While not sterile this product will keep for 
a long period. The long continued heat should destroy most 
bacteria and the addition of sugar acts as a preservative. 

An unsweetened condensed milk meant for immediate use is 
put on the market by many condensing companies. The process 
of manufacture is essentially the same, with the exception that 
no cane sugar is added, and the concentration is a little over 
three times. It is usually sold in glass jars capped with paper 
caps, similar to fresh cream, and will remain sweet and fit for 
consumption as long as fresh cream. 

Evaporated Milk. — Evaporated milk is an unsweetened con- 
densed milk sold in hermetically sealed cans. As no cane sugar 
is added, it depends entirely on sterilization for its keeping 
quality. The raw material is held in heating wells for ten to 
twenty minutes, then is run directly into the vacuum pan where 
it is concentrated two and a quarter times. After cooling, the 
evaporated milk is immediately put into cans and sealed. The 
hermetically sealed cans are sterilized at a temperature of 235 F. 
for one-half hour. While cooling, they are subjected to shakers 
to mix the jelly. This agitation breaks up any coagulum which 
may have formed during sterilization. The cans are finally 
placed in a curing room where they are kept for thirty days, 
after which they are examined before being placed on the 
market. As this product is sterile it will keep indefinitely. 



FOOD INDUSTRIES 227 

Concentrated Milk. — The Campbell process of concentrating 
milk has placed upon the market in recent years a small amount 
of milk, relatively free from bacteria, and which can be pur- 
chased at the price of ordinary milk. The best fresh milk which 
can be obtained is used. After being tested the raw product is 
put through the centrifuge, in order to clarify it from stable dirt 
and to separate the cream and skim milk. The cream is pas- 
teurized, while the skim milk is heated for two or three hours 
at a temperature of 140 F. during which a continuous blast of 
filtered air is driven through it. Evaporation is continued until 
three parts of the original product is condensed to one part of 
the concentrated skim milk; after which the pasteurized cream 
is added. The product is placed upon the market in small bottles 
to which three parts of water must be added to give the original 
consistency. On account of the low temperature used, concen- 
trated milk has not materially changed in composition and after 
the addition of water, it appears to have the properties of ordi- 
nary fresh milk. According to Professor Conn, the method of 
using combined heat and aeration destroys most of the bacteria, 
especially those of specific diseases, and gives a relatively safe 
milk even for infant feeding. On account of its concentration 
such milk when kept below 50 F. will last for a week or ten 
days. 

Milk Powders. — The process of reducing milk to the powdered 
form has become quite an industry in recent years. To obtain a 
successful product, the milk must be desiccated at a low tempera- 
ture in order to prevent as little chemical change as possible from 
taking place. This is frequently carried out by drying it in a 
thin film on metal plates in vacuo. The resulting creamy white 
powder will unite readily with water to give the original con- 
sistency of the milk. On account of the fat, powders prepared 
from whole milk will not keep indefinitely unless placed in cold 
storage; those from skim milk have been found more satisfac- 
tory. They are used to a large extent for cooking, especially 
where fresh milk cannot be obtained. 



228 FOOD INDUSTRIES 

BY-PRODUCTS OF THE BUTTER INDUSTRY. 

The chief industry using milk is the butter industry which 
has been described in Chapter XIII. The most important by- 
products of this industry are mentioned below. 

Skim Milk. — From whole milk the fat is separated in butter- 
making very largely at present by the centrifuge. With this 
method only a trace of the other constituents is removed with 
the fat; this leaves the skim milk rich in protein and carbo- 
hydrate. As skim milk contains all the normal ingredients of ordi- 
nary milk except fat, it can very readily be used for cooking pur- 
poses, or as a beverage for people who find cream hard to digest. 
As the law, however, frequently forbids the selling of skim 
milk, it has been utilized to a great extent for cattle food or in 
many cases it is thrown away. This is a waste of valuable 
material for the protein and lactose can be recovered by com- 
paratively simple methods. 

Dried Casein. — The skim milk is run into a vat and a small 
amount of sulphuric or acetic acid is added. This precipitates 
out the caseinogen in the form of a curd which can readily be 
removed from the whey, washed, pressed, dried and sold as 
dried casein. It is used in the paper, leather and textile indus- 
tries, as an ingredient of paints, glues, and cement, and for the 
manufacture of imitation ivory articles. 

Milk Sugar. — After the removal of the caseinogen, the water 
may be evaporated (over hot water) from the whey until the 
lactose crystallizes out. It is generally reduced to the powdered 
form and is much used in pharmacy and for infants' and invalids' 
food. 

Buttermilk. — Buttermilk is the fluid which is left after churn- 
ing in the process of butter-making. It is commonly used as a 
food for young calves and pigs, and occasionally as a beverage, 
especially during the summer months. The chief point in which 
it differs from milk is its poverty in fat and its increase in 
acidity, due to the formation of lactic acid which rarely exceeds 
0.5 per cent. It is comparatively easy to digest on account of 



FOOD INDUSTRIES 229 

the absence of fat and the changed condition of the caseinogen, 
which exists in a finely flocculent form. 

Artificially Soured Milk. — A milk which has been artificially 
soured by the addition of lactic acid ferments can now be found 
on the market, or can be prepared at home. It has been highly 
recommended by Metchnikoff. The product is prepared by 
pasteurizing pure fresh milk. The temperature is then lowered, 
cultures of lactic acid bacteria are added and the mass is held at 
ioo° F. for several hours. It is then bottled and sold under a 
trade name. 

CHEESE. 

Historical. — Cheese has been known as a valuable food for at. 
least one thousand years before the Christian era. It is believed 
to be one of the oldest products manufactured from milk and 
probably owes its origin to the accidental storing of milk curd. 

In the early historic days of the Roman Empire, it formed an 
important article of diet and is still used as a chief source of 
protein by the Italians as well as many other European nations. 
It is largely manufactured at the present time in France, Italy, 
Germany, England, Switzerland and Holland. The Americans 
produce large quantities of cheese especially in New York and 
Wisconsin, but do not as a nation consume as much as the 
Europeans. 

The industry in America was started in a small way, prin- 
cipally by immigrants who sought to earn a livelihood in the 
New World by the same occupation that they had carried on in 
their native land. This is particularly true of the cheese indus- 
try in Wisconsin, which owes its origin to the settlement of 
twenty-seven Swiss families during 1845, i n the rough hilly 
country of Greene County. For a long period the wives and 
daughters of the home were the cheese makers, but like many 
other industries, it was gradually transferred to the manufac- 
turer. 

The product is prepared from milk by processes which elim- 
inate water, and gather a large part of the solids together, in 
such a form that the nourishment is retained and capable of 



23O FOOD INDUSTRIES 

being preserved for varying periods of time. Many varieties are 
made at the present time. Cow's milk supplies most of the raw 
material, although the milk of the ewe and goat are used largely 
abroad for the manufacture of certain well known cheeses. As 
a rule, milk is used in its natural condition and the product is 
then known as whole-milk or full cream cheese. Cream cheese 
is made from milk and cream, while skim-milk cheeses are manu- 
factured from milk from which part of the fat has been re- 
moved. 

Whatever the kind of milk used, the general process of manu- 
facture is the same. The raw material must be treated in such 
a way as to precipitate the caseinogen in the form of a curd. 
This may be accomplished in two ways; by the natural develop- 
ment of lactic acid and by "the addition of rennet. The first 
variety known by some such name as pot cheese or cottage 
cheese is not a true cheese, as it has been prepared without the 
use of rennet, which is essential in cheese-making. This type 
cheese is prepared more frequently in the home, is soft in texture 
and has poor keeping quality. The second variety represents 
the many kinds of domestic and foreign cheese found in the mar- 
ket. 

Composition of Cheese. — Generally speaking, the composition of 
cheese is about from one-third to one-quarter each of water* fat 
and protein, with a small amount of mineral matter. The protein 
is largely predigested having been changed to casein by the action 
of rennet. Only a small amount of unchanged caseinogen can 
be found while in many well cured varieties, through the action 
of micro-organisms, part of the casein has been further changed 
to meta-protein, peptone and amino-acids. The mineral matter 
consists of the salts of milk with a small addition of common 
salt to improve the flavor. 

Cheese-making.— The large cheeses found in the American mar- 
ket are prepared by processes more or less copied from the Eng- 
lish Cheddar Process. Cheddar cheese was first made in the 
village of Cheddar, England, about 250 years ago. It has grad- 



FOOD INDUSTRIES 23 1 

ually grown in popularity until the manufacture has now spread 
over the civilized world. 

Process Used in Cheddar Cheese. 
I. Straining milk. '] 

II. Ripening— (82 ° -86° F.). 

III. Mixing rennet. 

IV. Clotting. 
V. Cutting. )■ Lactic acid fermentation. 

VI. Stirring. 
VII. Cooking 98 F. 
VIII. Removing part of whey. 
IX. Cheddaring or matting. 

X. Grinding. 
XI. Salting. 
XII. Pressing. 
XIII. Curing. 

The preliminary treatment of milk is of the greatest impor- 
tance. Successful cheese-making depends to a great extent on 
the purity of the raw material. Great losses are frequently 
caused by carelessness in the production and handling of the 
milk supply, for the quality of the milk in respect to its cleanli- 
ness, determines largely the quality of the product that can be 
manufactured from it. The same cleanliness should be observed 
as in the production of market milk, clean and healthy cows and 
milkers, sanitary conditions of stable, utensils and other appara- 
tus. Special attention should be given that no odors can be 
absorbed from manure, pig pens or silos and that the cow has 
not eaten strong smelling food, such as onions, garlic and the like. 
As quickly as possible after being drawn from the cow, milk 
should be strained and cooled. To assist the escape of volatile 
matter, it is sometimes aerated by being poured through the air 
from one container to another. Stirring also helps the escape of 
animal odors as well as prevents the cream from rising to the 
top. As lactic acid is desired, milk is allowed to ripen naturally 
or by the addition' of a starter, at a temperature of 82°-86° F. 
Tests are made from time to time until the desired acidity has 
16 



232 FOOD INDUSTRIES 

been developed. The milk is then run into shallow rectangular 
tanks, so arranged that they can be readily tilted, and containing 
pipes through which hot water can be circulated. A tempera- 
ture of about 85 ° F. is maintained. While heating the milk is 
constantly stirred with paddles to prevent the cream from rising 
to the top. If any coloring matter is to be added it is put in at 
this time. When thoroughly mixed and of the desired tempera- 
ture, the coagulative agent rennet, is added and the mass is 
again stirred for a few minutes and is then allowed to rest. 

The active principle of rennet is found in the lining of the 
stomach of milk fed animals. As a rule it is obtained from 
calves although it has been taken from pigs and puppies. Through 
the action of rennet, the conjugated protein caseinogen is split 
into simple proteins, casein and pseudo nuclein, thus making 
cheese a predigested food. The activity of rennet is greatly 
assisted by keeping the mass at body temperature, and by the 
successful ripening of the milk in an earlier stage. The clot or 
curd as it is known to the manufacturer, forms in about ten to 
fifteen minutes, but is usually allowed to stand one-half hour 
before it is put through the process of cutting. It is then firm 
enough to break with a clean fracture, when gently pressed with 
the finger. 

Until recent years, the curd was simply broken into irregular 
pieces with the hand or some instrument, in order to allow the 
escape of the whey. Experimentation has proved that there is 
less loss in the fat content, if the curd is cut into uniform pieces. 
The process is now carried on by curd knives which cuts the 
mass into small cubes. As the whey makes its escape, the cubes 
sink to the bottom of the vat and are kept from uniting by a 
gentle agitation of the entire mass. 

In order to facilitate the further separation of the whey, the 
temperature is raised to 98°-ioo° F. This shrinks the curd until 
it is about one-half of its former size and causes the development 
of more lactic acid. When sufficient acid has developed, the whey 
is again removed and the curd is allowed to mat together, various 
changes taking place during the process. The curd is then 



FOOD INDUSTRIES 233 

ground, in order to reduce it to particles of convenient size for 
receiving the salt and pressing it into shape. 

The salt is added principally to give flavor. It has, however, 
another influence, for salt having a great attraction for water, 
the curd is hardened. The mass is next put into a press for 
twenty-four hours to give it shape. After being taken from the 
press it is put into the curing room, where it undergoes fermen- 
tation for four or six weeks or longer. During this time the 
cheeses are turned at frequent intervals and are rubbed on the 
outside with whey butter, a fatty liquid which rises to the top 
of the quietly standing whey. 

Curing. — As cheese is not eaten for its nutritive value alone, 
but more frequently for the strong appetizing taste, this part of 
the process is most important. It consists in subjecting the 
cheese to the action of micro-organisms, which in their desire for 
food, decompose material giving rise to characteristic flavors. 
During this series of fermentations which are not altogether 
understood, gases develop which cause holes to be formed in 
the cheese. The ripening process is carefully guarded as to 
temperature so it will not proceed too rapidly or too far, in 
which case putrefactive fermentation is apt to set in. . 

As much of the success of cheese-making depends on the 
curing, bacteria and molds are now being carefully studied in 
connection with this industry. Methods once established by 
which ripening can be controlled, will insure a uniform product, 
an extension of the manufacture of certain varieties of cheese, 
and a saving of much money to the industry. 

For information in regard to the manufacture of well known 
cheeses, such as Roquefort, Edam, Camembert and Brei, see a 
standard book on dairy products as Milk and Its Products by 
Wing or The Practice and Art of Cheese -making by Van Slyke 
and Publow. 

Uncured Cheeses. — Several varieties of soft uncured cheeses 
may be found on the market, of which Neufchatel and Philadel- 
phia cream cheese are the best known. They are prepared by 
coagulating ripened milk with rennet, allowing the curd to 



234 FOOD INDUSTRIES 

develop a mild acidity, after which the surplus moisture is re- 
moved by drainage and pressure. The curd is then ground, 
salted, molded into shape and wrapped in thin paper and tinfoil. 

Adulteration. — The only extensive form of adulteration prac- 
ticed is the substitution of lard for the usual amount of fat. 
Lard and skim milk can be mixed together with coloring matter, 
put through a process first to emulsify the lard, after which reg- 
ular processes of cheese-making can be carried out. 

Although adulteration has not been practiced to any large 
extent, much misbranding of cheese has been discovered in the 
United States. Cheese manufactured in this country has been 
frequently found to bear a label conveying the impression that 
the article is of foreign make, also, that the cheese has been made 
of cream and milk, when only whole milk has been used. 



CHAPTER XVIII. 



PRESERVATION OF FOODS. 

Methods used in preserving food material may be classified 
as follows : 

Drying. 
Physical <j Cooling. 



Sterilization and exclusion of air. 

( Sugaring. 
! Salting. 
Chemical { Smoking. 

I Use of fats and oils. 
1^ " " spices. 

f Borax and boracic acid. 
| Sulphurous acid and salt. 
Use of Preservatives <j Benzoic " " " 

| Salicylic " " " 

(^ Formaldehyde. 

The attempt to preserve food material has been practiced from 
the earliest ages, many centuries before the cause of decay was 
understood. This custom undoubtedly arose from the desire to 
hold provisions obtained in a successful chase or during an abun- 
dant harvest, for periods of famine, pestilence and inclement 
weather. Modern life is making this subject of vast importance, 
for the crowding of people into large cities necessarily means the 
carrying of food for long distances, and present habits of living 
demand the open market for twelve months in the year. To 
meet this problem, bacteriology has been called upon to make, 
plain the habits of the micro-organisms, which live on food and 
are the cause of the decay. 

DRYING. 

Drying is the oldest and simplest method, the principle being 
exclusively the withdrawal of water. Mold can live on a very 
small amount of moisture for it is frequently seen growing on 
damp floors, walls,- cloths, food and the like. Bacteria demand 
considerable water and will not grow unless well supplied. They 
need a medium that is practically liquid, for they are only able to 



236 FOOD INDUSTRIES 

absorb food in a fluid condition. Many types of bacteria will 
cease to grow when the amount of water falls to 30 per cent, 
and all stop developing when it is below 25 per cent. 

Nature uses this method of preservation, for when the grain 
is ripening much of the moisture which was present in the green 
stage gradually disappears, leaving the mature grain shriveled 
and dry. If this were not so, putrefaction would soon take place. 
Much of our food material classed as non-perishable, such as 
cereals, starch, sugar, flour and meal is preserved in this way. 
That they are good food for micro-organisms can readily be 
seen by their rapid decomposition when water is added. 

Drying seems to be very much better adapted to fruit and 
vegetables than it does to protein matter, although meat is fre- 
quently shredded and dried by exposure to sunlight, in many 
parts of the world and to some extent in the arid regions of this 
country. It should only be practiced in climates where there is 
little moisture in the atmosphere, or the meat will spoil before 
it becomes sufficiently dry, and in districts far removed irom 
crowded habitation where bacterial life is not abundant. While 
dried meat has a fair amount of palatability and has maintained 
all of the nutritive properties, it is not as digestible and looks 
less attractive so will never be popular. Dried, smoked or 
chipped beef are common articles of commerce, but either smok- 
ing or the use of condiments has been added to the drying 
method. This method is also used with the addition of salt to 
produce a form of protein known as pemmican used extensively 
by Arctic explorers. 

With fruit and vegetables drying is very effective. The sim- 
ple method of exposing fruit to the sunlight was practiced uni- 
versally until modern times. In California and such sections as 
are free from rain and excessive moisture, open-air drying is 
still extensively employed. The fruit is cleaned, cut, placed on 
wooden trays, sterilized with sulphur and placed in the sunlight 
for five or six days or until sufficiently dried. In other parts of 
the United States, indoor drying is now used, principally on 
account of the moisture present in the atmosphere. 



FOOD INDUSTRIES 237 

Several methods are used at the present time: 

I. Fruit is put in large drying chambers and currents of 
warm air are passed over it. The water is withdrawn until 25 
to 30 per cent, only is left. 

•II. Evaporation by vacuum dryers is more rapid but the color 
is changed. This may be overcome by the use of chemical 
means such as the use of H,S0 3 , called sulphuring. 

III. Hydraulic pressure has been found to be very effective, 
but is little used. 

Many methods of drying are trade secrets. 

These modern methods have greatly increased the number of 
dried products on the market. One can now find in commerce 
peas, beans, apricots, apples, plums, raisins, figs, berries of all 
kinds, compressed vegetables, soups with or without meat, and a 
vast number of similar products. Present methods are also far 
more sanitary. The old-fashioned habit of sun-drying often 
meant an exposure to flies and dirt of all kind. The flavor of 
dried fruit is to some extent altered, due to oxidation, but the 
nutritive value is the same as in fresh fruit. 

COOLING. 

The principle with this method of preservation is surrounding 
food with conditions unfavorable for bacterial development. The 
thermal death point of micro-organisms ranges between wider 
limits than any other form of life. Boiling does not kill all, 
neither does freezing. The best temperatures at which to hold 
food in cold storage, or to which it should be raised with sterili- 
zation, are now being carefully studied. 

Advantages of Cold Storage. — I, No nourishment is taken 
from food. 

II. No foreign matter is added. 

III. No new taste is imparted so the flavor is not greatly 
changed. 

IV. The digestibility is not diminished. 

V. A large quantity of perishable goods can now be kept that 
were formally thrown away. 



238 FOOD INDUSTRIES 

Disadvantages of Cold Storage. — I. The keeping quality is im- 
paired especially when too low a temperature has been used. 
The physical condition is frequently altered so bacteria can more 
readily act upon it as with meat or fish. Such food should be 
consumed as quickly as possible when taken from refrigeration. 

II. Fruit deteriorates rapidly after having been in cold stor- 
age. This is frequently caused by a large amount of moisture 
condensing on the surface of cold fruit when taken into a warm 
place, thus making the conditions most favorable for mold 
growth. 

III. It has led unscrupulous dealers to hold back products for 
~. high prices. 

In spite of these disadvantages, cold storage has been one of 
the best methods so far used for preserving foods. Beginning 
in i860, its use has spread enormously and has made possible 
the uniform distribution of fresh foods, such as meat, poultry, 
eggs, milk, fruit, vegetables and the like throughout every part 
of the country. By an interchange of the surplus with foreign 
nations, it has vastly improved the world's food supply and has 
greatly remedied the enormous waste, in many sections of both 
hemispheres. 

Manufacturers' methods of coolings are either employment of 
ice or the expansion of compressed gas, as used in the ammonia 
process. The housewife must as a rule depend upon an ice 
chest which is generally kept too warm. The temperature of an 
ordinary refrigerator registers from 50 to 6o° F., whereas it 
should be kept below 50 ° F. 

Precautions in Care of Chest. — I. Do not wrap ice in news- 
paper. It is only in melting that low temperature is maintained. 

II. Keep ice chest well filled with ice. 

III. Keep the chest as dry as possible as cold damp air harbors 
many low forms of plant and animal life. 

IV. Charcoal should not be utilized for lining as it soon be- 
comes clogged and makes a fine incubator for bacteria. 

V. Wash frequently with warm water and a neutral soap. 



FOOD INDUSTRIES 239 

STERILIZATION AND EXCLUSION OF AIR. 

See Chapter XIX. The Canning Industry. 

SUGARING. 

Preserving by means of sugar is not used to as large an extent 
to-day as it was in former years. The great improvements 
achieved by canning manufacturers have made their products so 
popular that they have largely taken the place of the old-fashioned 
preserves. 

The principle of the sugaring method is surrounding food with 
conditions unfavorable for growth of micro-organisms. Bac- 
teria do not grow well in a pure sugar solution unless it is very 
weak. If the solution be strong, development is entirely pro- 
hibited. Yeasts will sometimes grow and cause fermentation to 
set in, but this cannot take place if the sugar is as high as 40-50 
per cent. The old-fashioned housekeeper's recipe usually read — 
"A pound of sugar to a pound of fruit," thus the product was as a 
rule protected against fermentation. It was quite possible, how- 
ever, for mold to grow, but the formation always occurred on 
the surface and could readily be removed. 

The great disadvantage with this method is the altered taste. 
Sugar is added in such large quantities that the strength of its 
flavor conceals or destroys other flavors that are desired, as the 
pleasant acidity of many fruits. A second inconvenience is the 
large quantity of sugar that is required in order to preserve a 
small quantity of fruit, hence the use of it is very expensive. 
Preserved fruits are used to-day, only as a sweetmeat. 

It has been found possible to preserve meat and fish by the 
use of sugar alone. Although this method has never been used 
with protein material in America, it is still customary in Por- 
tugal to preserve fish, as the salmon, by splitting, cleaning and 
sprinkling the interior with sugar. It is said that fish prepared 
in this way can be kept for a long time with a perfectly fresh 
flavor. 

SALTING. 

The keeping of food material with salt has been used from 
very early times. The discovery of its preservative action was 



240 FOOD INDUSTRIES 

probably accidental, due to the finding of animal carcasses em- 
bedded in the saline deserts of Asia. Ancient wine makers fre- 
quently used salt water with the object of keeping their product 
for a longer period, and Pliny speaks of flesh food being treated 
with salt and meat being preserved with brine. The custom of 
salting fish was also known to the Greeks and Romans, but it 
seemed to have been used more as an incentive to the consump- 
tion of wine than because of any wish to add to the keeping 
quality of the product. 

The principle of its protective power lies largely in the with- 
drawal of moisture, for salt has a great attraction for water. 
Bacteria cannot develop in food impregnated with salt so it can 
be preserved indefinitely by this method. 

A variety of foods can be salted as olives, nuts and pickles, but 
this process has been used to the greatest extent with meats and 
fish. 

Different methods may be used : 

I. Rubbing dry salt into meat. 

II. Pickling or the use of a saturated salt solution. 

III. Salting and the addition of smoking or drying. 
Advantage. — I. Salt is harmless and is needed in the diet. 
Disadvantages. — I. The flavor is greatly changed. 

II. The physical nature of meat or fish is changed, fiber is 
toughened so the product is not as digestive. 

III. Nourishment is lost as certain constituents of protein 
matter are soluble in a salt solution and are lost in the brine. A 
saturated salt solution also renders protein more or less insol- 
uble, hence it is not all available as food. 

On the whole, salting has not been found satisfactory. The 
destruction of taste and the reduced nutritive value are serious, 
and other methods of preservation have to a great extent taken 
its place. 

SMOKING. 

The art of smoking meat and fish to assist in its preservation 
has been practiced from remote ages. The custom probably 
originated from the habit of suspending such food material 



FOOD INDUSTRIES 



24I 



within the tent or primitive dwelling. Being close to an open 
wood fire, smoke arose saturating the hanging material and not 
only gave it an agreeable taste, but greatly assisted in the keeping 
quality. This simple practice is still largely followed in isolated 
sections. Small smoke-houses are frequently found in many 
parts of the country, where meat or fish can be laid across slats 
near the roof and smoke from a wood fire allowed to pass over.it. 




Fig. 61.— The Sausage Smoke House. (Courtesy of Armour & Co., Chicago, 111.) 

The preservative action is noW known to be due to certain 
products present in the smoke, such as creosote, which contains 
a bactericidal substance known as guaiacol. Formaldehyde and 
acetic acid are also present in smoke, but as they are extremely 
volatile, they are of little use. Creosote being less volatile 
remains on the exterior of the meat and acts as a violent germi- 
cide, while being perfectly harmless to the human consumer of 
the product. Since many woods also yield turpentine on burn- 
ing, it is necessary to select beech, hickory, oak or such woods 
as yield creosote and not organic compounds which would affect 



242 FOOD INDUSTRIES 

the flavor. Water plays an important part in the production 
of creosote so generally the wood is used in the green state 
(Fig.6i). 

Smoking does not protect against all forms of micro-organ- 
isms. Mold can attack food preserved in this way, but it is 
usually only on the surface and can readily be removed with a 
cloth dampened with lard or sweet oil. Canvas-covered meats 
are less likely to be attacked by mold. As smoking does not 
reach the interior, only material free from contamination should 
be used. 

It is quite customary to combine salting and sugaring with 
smoking as in sugar cured hams. If such products are of a 
high grade, they are immersed in a pickle compound of salt, 
salt-petre, sugar and spices for forty to sixty days, after which 
they are placed in a smoke-house for three days. This process 
is excellent but it is long and increases the cost, so a quicker, 
cheaper method is occasionally substituted. Brine is pumped 
into the ham and the product is then treated with smokine. This 
preservative contains minute particles of creosote in solution 
and may be applied by a brush or by dipping meat quickly into 
the solution and afterwards drying it. This method is not as 
effective as the use of the old-fashioned smoke-house and the 
cresote is more likely to penetrate. 

USE OF FATS AND OILS. 

Foods which do not contain a large amount of fat are very 
good put up in oil, sterilized and sealed to prevent the oil from 
becoming rancid. A coating of oil is also frequently used to 
preserve foods by the exclusion of air. This method has been 
used largely abroad where birds are dried and saturated with 
oil ; goose-livers similarly treated are sold as "pate-de-f oie- 
gras." These products are considered great delicacies. In Italy 
wine is often covered with oil to prevent bacterial action, and in 
Arctic regions many kinds of meat are frequently preserved in 
this way. Possibly the most common food on our market put 
up in oil is the sardine although tuna fish, salmon, mushrooms, 
truffles and artichokes are also important products. 



FOOD INDUSTRIES 243 

The name sardine was originally given, to a variety of fish 
found in the Mediterranean near the Island of Sardinia but the 
commercial usage now includes several varieties, the French 
sardine being the young of the pilchard, and the American, 
young herring. 

During the process of manufacture the fish are carefully 
sorted into sizes, cleaned, placed in brine, washed in fresh water, 
dried in the open on trays, immersed in oil, boxed and sterilized. 
Olive and peanut oils are largely used abroad while cottonseed 
is frequently substituted, especially in America. As a rule the 
French sardine receives greater care in the manufacture and is 
supposed to improve with age caused by the blending of fish, oil 
and flavoring. 

This method of preservation is also used in Germany in the 
manufacture of sausages. In the German market, two types of 
sausage can be found: those so rich in fat that they can be kept 
for some time; and those which are lean and must depend upon 
the preservative influence of the high content of spices. The 
casing in both types is more or less impervious to any material. 

USE OF SPICES 

Spices were originally added to food to change or modify the 
flavor, but it has been found that they exercise a powerful pre- 
servative effect. See Chapter XXII. Spices. 

ALCOHOL. 

Alcohol makes all protein matter insoluble thus killing all 
bacterial life. For this reason, it is used largely in preserving 
biological specimens. To a slight extent it is also used for foods. 
Fruit of all seasons can be put down in an alcohol solution and 
preserved indefinitely. 

USE OF PRESERVATIVES. 

It is well known that certain chemicals when added to food 
have a restraining influence upon bacteria, yeast and molds 
which are associated with its decomposition. Some simply pre- 
vent the further development, others act as strong bactericidal 
agents. In the early days of the canning industry, they were 



244 FOOD INDUSTRIES 

largely used but modern methods of sanitation and sterilization 
by heat have proved so much more reliable and less expensive, 
that manufacturers of legitimate products have now almost en- 
tirely abandoned their use, regardless of the Pure Food Law. 

The harmful nature of these chemical compounds has been ar- 
gued for and against for a long period. At the present time prob- 
ably all agree that their use is absolutely unnecessary for goods 
that are to be consumed within a short period. There is still, 
however, much discussion as to their use in such products as 
chili-sauce, ketchup, apple butter and other foods classed as rel- 
ishes. These products have been cooked thus making them more 
susceptible to bacterial action after being opened. As they are 
usually held for a length of time, too frequently under careless 
conditions, they are apt to become undesirable articles of food. 
For this reason, benzoate of soda or other preservative is fre- 
quently added in small amounts. 

Arguments advanced in favor of their use are: 

I. These antiseptics are harmless when used in small amounts. 
One part salicylic acid in 1,000 is not injurious and may be 
beneficial in warding off intestinal diseases. 

II. They are found occurring naturally in many of our fruits 
such as currants, cranberries, raspberries and crab-apples. 

III. These antiseptics are frequently developed during manu- 
facturing processes especially where sterilization by high tem- 
peratures is necessary. 

Arguments against their use : 

I. They are not violent poisons, but are believed to be unde- 
sirable as they are antifermentatives so interfere with the diges- 
tive ferments. 

II. They are irritants so stre apt to injure the mucous mem- 
brane of the stomach and intestinal canal. 

III. The blood has for its chief function oxidation. These 
chemical compounds interfere with the blood doing its work of 
oxidation. 



FOOD INDUSTRIES 245 

1 

IV. The amount is not always small. 

Possibly the strongest reasons for prohibiting their use are 
that it may lead to carelessness in manufacturing processes and 
to the use of inferior material. Neither can they be regarded as 
"cure-alls" for they do not affect ptomaines which cause disease. 

Artificial Sweetening. — Saccharine has been largely used for 
sweetening syrups, preserves, jams, jellies, canned goods and 
similar products. It is a glistening white powder resembling 
sugar, but with a much greater sweetening power, thus making 
it a cheaper agent to use. Saccharine is obtained by the oxida- 
tion of one of the coal tar products and has no food value. It 
is believed to be an irritant so its use has been forbidden. 

Artificial Coloring. — The employment of artificial coloring in 
connection with food has been practiced for the past fifty years. 
The colors have included animal, vegetable and mineral dyes for a 
long period and recent years have added an innumerable number 
of coal tar dyes to the list. The animal and vegetable dyes have 
included cochineal, annatto, turmeric, logwood, saffron and carrot 
juice, which are generally supposed to be harmless. At present 
the only mineral dyes being used to any extent are copper sul- 
phate in green vegetables and fruit, oxide of iron in coco, con- 
fectionery, condiments, sausages and the like and Prussian blue 
in sugar refining. 

Copper sulphate is generally considered to have a deleterious 
effect on the consumer but it is not known to be cumulative as in 
the case of lead. Its use is prohibited in Germany, Austria 
and Hungary and is limited in many other European nations. 
The United States does not forbid its being added to food 
material but the amount must be stated. 

The coal tar dyes are unlimited in variety and are used ex- 
tensively in confectionery, jellies, jams, meat, dairy products, 
wines and non-alcoholic beverages. Usually the amount is very 
small rarely exceeding one part in one hundred thousand and 
for this reason, it is almost impossible to form an opinion in 
regard to whether or not it is injurious to health. While such 
coloring matter may not be detrimental to the consumer, the use 



246 FOOD INDUSTRIES 

is unfortunate for it enables the manufacturer to place inferior 
goods upon the market for high grade material. Articles of 
food are much preferable in their natural color, and it is 
unfortunate that the housewife so frequently prefers highly 
colored goods thus encouraging the use of artificial coloring 
matter. 



CHAPTER XIX. 



THE CANNING INDUSTRY. 

Historical. — The process of food preservation by canning was 
invented in 1810 by Nicholas Appert of Paris. The underlying- 
principle of this method, the destruction of all life by means 
of heat followed by the exclusion of air by hermetically sealing, 
was established by the experimental work of Spallanzani, in 
1765. By placing various nutritive liquids in tubes, sealing, and 
boiling them for an hour, he discovered that the liquid remained 
unchanged, as long as the seal was unbroken. 

/During the warfares of Napoleon, much dissatisfaction occurred 
in regard to the food that his army was obliged to eat while on 
the march. An investigation followed which led to the offering 
of a prize of 12,000 francs to any man who could keep food 
indefinitely in its natural condition without adding the preserva- 
tives then in use, which included salt, sugar, vinegar and smoke. 
It was won by Appert, who, after long practical experience in 
confectioneries, kitchens, breweries and distilleries, had been 
working for many years along the line of food preservation, using 
the theory advanced by Spallanzani. Food material was placed 
in air tight containers after it had been subjected to such a de- 
gree of heat that the contents had been thoroughly sterilized. The 
apparatus used by Appert was necessarily very crude but his 
discoveries laid the foundation for one of the greatest industries 
of modern times. 

About the same time, Peter Durand obtained a patent in Eng- 
land for preserving meat, fruit and vegetables in tin cans, and 
shortly after several other manufacturers introduced similar 
methods. The theory upon which these men worked was, that 
the oxygen contained in air was the destructive agency and its 
exclusion alone would preserve food which had been cooked. 
It was not until the time of Tyndall and Pasteur that the real 
cause of putrefaction was understood. The industry was estab- 
lished in the United States by Ezra Daggett, who after learning 
the trade abroad canned salmon, lobsters and oysters in New 
17 



248 FOOD INDUSTRIES 

York in 1819. Shortly afterward William Underwood started 
to pack tomatoes, and in 1837 Isaac Winslow began experimenting 
with the canning of corn in Portland, Maine. Spreading grad- 
ually throughout the east, this industry was finally introduced into 
the middle west about the time of the breaking out of the Civil 
War and within a year or two, we find its establishment in Cali- 
fornia. An enormous impetus was given to canning when it was 
discovered that canned goods were vastly superior to dried food 
in palatability, for army use. The growth of the industry since 
that time has been very rapid and at the present time, canneries 
are scattered throughout the United States. Along the Atlantic 
Coast, large quantities of vegetables, meat and fish are preserved. 
Oregon and Washington supply much of the salmon, Chicago 
packs largely meat, while California furnishes fruit and vege- 
tables of the highest grade. 

The rapid growth soon led to new and better methods of making 
cans, great improvements in machinery, skilled workers and much 
experimentation in regard to the best methods of sterilization. 
In the latter work manufacturers have been greatly assisted by 
scientific investigation. 

While the United States puts out enormous quantities of certain 
products, such as corn, tomatoes and salmon, European coun- 
tries have a considerably larger variety of articles. Numerous 
combinations of mixed vegetables, meat and vegetables and meat 
delicacies are placed on the market, one country alone having 
canneries whose output includes several hundred different items. 
The future possibilities of this industry, both at home and abroad, 
are very great if by rigid inspection, only canned foods consisting 
of good wholesome material, packed with proper care under sani- 
tary conditions are placed upon the market. 

Process. — As before stated, the two principal points to be borne 
in mind in the preservation of foods by canning are: — 1st, the 
destruction of all micro-organisms and their spores by means of 
heat ; 2nd, the exclusion of air by hermetically sealing. As a rule, 
the can and food are sterilized at the same time but the details of 
the process necessarily vary with different products and in 



FOOD INDUSTRIES 



249 



various canneries. Fruit and vegetables should be selected when 
at their best, transported as quickly as possible to the factory and 
immediately sorted for quality. They are then washed, treated 
according to the product and placed at once in cans. Care is 
given that the cans are filled full, then closely covered with the 
exception of a small hole for exit of steam. They are then 
subjected to the temperature of boiling water or higher according 
to the material. The hole is immediately closed with solder, the 




Fig. 62.— Stock Boilers. (Courtesy of the Franco- American Food Co.) 



cans reheated and allowed to cool. Some factories accomplish 
the same result by means of a steam heated "exhaust box," which 
withdraws part of the air in the filled cans, before they are sent 
to the capping department. With either method a partial vacuum 
is formed within the can which causes the end to be depressed. 
Should the process of sterilization be imperfect and bacteria or 
their spores be left within the can, fermentation soon starts in 
and the formation of gas causes the top to bulge. Canned goods 
are usually kept for one month and are then tested by striking 



250 



FOOD INDUSTRIES 



with the finger. Expert examiners are able to tell by the sound 
if a partial vacuum still remains. 

With the best manufacturers all cans which show the presence 
of gas are thrown away. In some factories, however, they are 
resterilized. This practice is dangerous, as injurious products 
may have developed which are not affected by reheating (Figs. 
62 and 63). 

Success of Canning. — There has been a great difference with 
various foods in regard to successful canning. Fruits are more 




Fig. 63.— Sterilizing Process. (Courtesy of the Franco-American Food Co.) 



subject to yeast and molds which are killed at a comparatively 
low temperature, so have given little trouble. Tomatoes, corn 
and peas, however, have been successfully canned only after 
much experimentation. Even after careful treatment and seal- 
ing, these products have frequently undergone the putrefactive 
changes that it was the purpose of canning to prevent. Through 
scientific investigation, the discovery was made that these vege- 
tables are invaded with bacteria, the spores of which will resist 



FOOD INDUSTRIES 25 1 

heat for a length of time. If when the can is sealed a single 
spore remains alive, it is capable of completely ruining the prod- 
uct in the course of time. For a long period it was thought 
impossible to can green corn, for that vegetable had given the 
manufacturer more trouble than any other product. With the 
aid of the bacteriologist, the problem has been completely solved. 
Corn is not only invaded by extremely resistant spore bearing 
bacteria, but the kernels are not easily penetrated by heat. Those 
which lie next to the can are easily sterilized but the interior 
layers do not heat readily. For this reason a thermometer is 
usually put in the center of a test-can and the temperature is 
carefully registered. It has been found necessary to use 250 F. 
for 65 minutes in order to kill all spores present. 

Regardless of the product, the success of canning depends on 
the sanitary conditions which prevail throughout the factory, the 
quality of the material and the rapidity with which it is handled. 

Meat Products. — In the canning of meat, the fore-quarter as a 
rule is used, the hind-quarter selling better as fresh meat. Al- 
though this may mean a poorer grade meat, it does not necessarily 
indicate that it is any less healthy. Before sterilization, meat is 
usually cut into uniform pieces, as different sizes would mean 
disintegration of the smaller pieces, before the larger ones are 
cooked, thus giving a bad appearance to the finished product. 
The meat is then par-boiled for 8-20 minutes to secure shrinkage 
before being put in cans. The further processes of sterilization 
and exclusion of air are quite similar to those used in other 
canning industries. 

A large variety of potted and deviled meat can also be found 
on the market. As the process of manufacture is usually a trade 
secret their exact composition is difficult to determine, but they 
are largely composed of beef or pork, mixed with spices and 
flavoring, the larger amount of condiments being used with the 
deviled varieties. 

Containers. — Manufacturers use either glass or tin in preserv- 
ing. The preference usually is in favor of glass but it is a ques- 



252 FOOD INDUSTRIES , 

tion whether this is warranted, except in certain products which 
cannot be preserved to the best advantage in tin. 

Advantages of Glass. — I. Food material such as fruit or vege- 
tables look very attractive. 

II. It contains no lead or other dangerous material. 

III. In the household it is much easier to handle. 
Disadvantages of Glass. — I. The jars to be strong must be 

made of thick glass which is likely to break with a sudden change 
of temperature. They also break easily if struck with a blow. 

II. They cannot be handled with automatic machinery. 

III. Transportation is difficult on account of the weight and 
liability to break. They occupy too much space. 

IV. It is frequently necessary to cover the glass with paper 
as light has a bleaching effect on some products. 

Caution. — When glass jars are used in the home they must 
be made air tight. This is a difficult thing to do especially where 
rubber bands are used. Old rubber bands have lost their elas- 
ticity so are not safe to use. It pays to buy new ones. As sul- 
phur has been used to impart elasticity and to keep the rubber 
from sticking, the new bands should be moistened before using. 

Advantages of Tin Containers. — I. They are light to handle 
and occupy less space in storing and during transportation. 

II. They are less likely to break. 

III. Products are protected from light. 

IV. They are much easier to make air-tight. 

V. Tin cans cannot be refilled. 

VI. If a good quality of tin has been used and the can carefully 
made, there is no danger of poisoning. 

Disadvantages of Tin Containers. — I. Tin cans are not prac- 
tical for use in the household. 

II. They are dangerous if a poor grade of tin has been used 
or the process of manufacture has not been thoroughly carried 
out. 

III. With such products as raspberries, cherries, plums and 
beets, they are not desirable as the tin coating is attacked resulting 
in a loss of color, flavor and quality. Salts of tin are also formed 



FOOD INDUSTRIES 253 

which are objectionable. For the protection of such products 
a recent improvement has been made by coating or lacquering the 
inside of the can. While such coatings are not perfect, they are 
a step in advance and further improvement will undoubtedly be 
made in the near future. 

According to work done by the United States Department of 
Agriculture,* such products as corn, peas, beans and tomatoes 
have little action on tin so a coating is unnecessary. 




Fig. 64. — Can Closing Machines. (Courtesy of the Franco-American Food Co.) 

On the whole there is practically little risk now in the use of 
tin, as the manufacture of cans has greatly improved. They are 
made of sheet iron which has been cleaned and rolled out to the 
proper thickness, dipped into acid to remove oxide, put quickly 
into water then dried, after which the sheet is dipped quickly 
into melted tin. Before being made into cans by machinery they 
are carefully examined. If the oxide has not been removed the 

* The Canning of Foods. Bulletin No. 151. Bureau of Chemistry. 



254 FOOD INDUSTRIES . 

tin will not stick, thus leaving the iron exposed to the action of 
organic acids occurring in fruits and vegetables. All imperfectly 
made sheets are rejected. The modern can is made with lock 
seams and outside soldering (Fig. 64). As the sealing in many 
cases is done by double seaming on the top, no solder is used 
except on the side seam. This overcomes possible contamination 
by solder in contact with food material. 

To insure the. safe usage of products packed in tin, it is abso- 
lutely necessary that the contents be removed after the can has 
been opened, to prevent oxidation. 

Adulteration. — Since modern methods of sterilization have been 
employed, the use of preservatives has been practically abandoned 
in the canning industry, as they simply add to the cost. Saccharine, 
bleaches and coloring matter now constitute the chief adulterants. 
Saccharine is frequently added to corn, tomatoes and peas to dis- 
guise the fact that sweet varieties of the garden vegetable have 
not been used. A bleaching agent is frequently employed to 
whiten corn, and peas are given a bright green shade by the 
addition of copper salts. During canning and on standing peas 
are apt to lose part of the chlorophyl through oxidation processes, 
which give them a yellowish appearance. Copper salts will unite 
with the nitrogenous constituents of the peas to form a compound 
with a brilliant green, thus restoring the original color, although 
the shade lacks the delicacy of the natural green. The coloring 
of peas is largely practiced in France, but as a rule is not used 
by American canners. Very little adulteration has been found 
in tomatoes except the addition of coloring matter such as coch- 
ineal or coal tar dye. The artificial coloring has been used to 
make inferior material appear as mature and high grade tomatoes. 

The adulteration of canned meat is probably more often prac- 
tised than with vegetables, but it has been found by no means 
common, by the Bureau of Chemistry. It consists largely in the 
substitution of cheaper meats and fat and the addition of starch 
to increase bulk and weight. Coloring matter and preservatives 
as borax, boracic acid are still occasionally found. 



CHAPTER XX. 



TEA, COFFEE AND COCO, 



\v 



TEA. 

Historical. — According to the writings of an ancient Chinese 
author, the virtues of tea were known in the Orient some 2,700 
years before the Christian era. Many legends exist as to its 
original home, some claiming that it was first grown in China, 
while others speak of its introduction into that kingdom from 
one of the neighboring provinces of India. 

For a long period it seems to have been used as a medicine 
rather than as a beverage. Gradually growing in popularity, 
however, it eventually became a national drink and the cultiva- 
tion of the tea plant for this purpose grew to be an important in- 
dustry in China, Japan, India and Ceylon. 

It was not until the later part of the-i6th century that the 
Dutch East India Co., in their journeys to the Orient, carried 
back to Holland some of the curiosities of the Eastern World, 
one of them being Chinese tea. Knowledge of it finally went to 
England and in 1657, we hear of the first tea-house being 
opened in Exchange Alley, London. For many years the 
price per pound was so high that tea was looked upon as a rare 
luxury, but by the latter part of the 17th century it was being 
imported from China in such large amounts, that it ceased to be 
a rarity. As the price lowered the annual consumption grew 
until at the present time Great Britain uses considerably more 
than one-half of the world's total production. Tea was intro- 
duced into the colonies as early as 1680, the price at that time 
being five or six dollars per pound, for the cheapest varieties. 

Cultivation of the Tea Plant. — The tea plant is a hardy ever- 
green shrub, which grows to a height of from twelve to fifteen 
feet in the wild state, but under cultivation it is usually dwarfed 
in order to stimulate the greatest possible growth of the young 
shoots. These yield the tender new leaves so desirable in tea- 
making. It will grow in a variety of climates, but the sub-trop- 



256 



FOOD INDUSTRIES 



ical appears to be the best, especially in sections where the rain- 
fall approximates fifty inches annually. The plant is usually 




Fig. 65.— The Tea Plant. (Courtesy of McCormick & Co., Baltimore, Md.) 

placed on a southern exposure, so the sunshine will protect it 
from cold, and in soil which has a certain water-retaining prop- 
erty. In China most of the tea gardens are small, each farmer 



FOOD INDUSTRIES 257 

producing enough for the consumption of his own family, while 
the surplus is sent to the market. Following this idea, the 
United States Department of Agriculture has strongly recom- 
mended the growing of tea on the farms of the South Atlantic 
and Gulf States. With very little trouble and expense, the 
southern farmer could at least raise enough tea for his own use, 
while the plant itself makes a hedge well worth cultivating for 
purely ornamental purposes. Farmers Bulletin, No. 301, "Home 
Grown Tea" gives many ideas as to the successful cultivation 
and manufacture of tea in the United States. 

In modern methods of cultivation, the plants are raised from 
seeds in nurseries and are set out in their permanent home in 
the open when about twelve inches high. According to climate, 
soil, etc., the first crop is borne in three or four years, and from 
that time, the shrub may be picked at regular intervals. It is 
customary to occasionally allow the plant to rest, thus insuring a 
longer life. 

General Classification. — The differences in the tea appearing 
on the market do not depend upon the variety of shrub, but 
rather on the size of the leaf and the way in which it is treated 
during manufacturing processes. According to the method of 
curing it is designated as: — 

I. Black tea, which has a dark, dull appearance. 

II. Green tea, which has a rather brilliant tinge due to the 
retention of part of the chlorophyl. 

For a long period, China so jealously guarded her tea gardens, 
that her green and black teas were supposed by foreign nations, 
to be produced from different species of shrub. That this idea 
was false was finally proved by Robert Fortune, who travelled 
in China on behalf of the Horticultural Society. 

Tea is also classified according to the size of the leaf (Fig. 66). 

I. Pekoe, which consists of the three young shoots at the tip 
and are known as flowery pekoe, orange pekoe and pekoe accord- 
ing to their size. As these leaves contain the least fiber and the 
most juice, they produce the finest grade of tea. 

II. Souchong is prepared from the leaves immediately below 



2 5 8 



FOOD INDUSTRIES 



the pekoe variety and makes a tea of popular price. Classes I 
and II are sometimes mixed when the product is known as 
pekoe-souchong. 

III. Congou is a cheaper variety prepared from the more 
fully developed leaves below the souchong size. In the Ameri- 




^ // 



C*. ^tyc/foryo feecor?c/) f, C O77O O is 
a one/ /b (m/xec/J /c/(oe j o,A>, c. g/ e 



fe/Co 



- ~5o&c r? o r? c? 



can market this term is sometimes used as a general name for 
China Black Teas. 

IV. Bohea is a name frequently applied to any larger leaf 
used for tea-making than the congou variety. This tea is no 
longer found in our market. 



POOD INDUSTRIES 



259 



v Processes of Manufacture. 
Beack Tea 
Leaves picked. 
Withered in the sun 
Rolled until soft. 
Fermented. 
Fired. 
Sorted. 



Green Tea 
Leaves picked. 
Withered in pans. 
Rolled until soft. 
Withered again. 
Sweated in bags. 
Slowly roasted. 

Picking. — The tea leaves are plucked entirely by hand, the 
operation generally being carried on by women and children. In 




Fig. 67.— Withering Tea Reaves. (Courtesy of The Spice Mill Publishing Co.) 

China and Japan there are several harvests. The first picking 
commences about the middle of April and gives delicate pale 
green leaves, which usually command a high price. About two 
weeks later, the bush is again ready to be plucked and again > a 
third and fourth picking follow, each harvest yielding leaves a 
little lower in quality. In Ceylon where there is practically no 
winter, picking takes place about every ten or twelve days the 
year round. 

Withering. — Whether small or large, the leaves are of the same 



260 



FOOD INDUSTRIES 



general structure. All consist of a certain amount of fibrous 
material which must be softened by rolling. In order to make 
this operation easier, the leaves are first withered, either indoors 
or by exposure to the sun, until part of the moisture has evap- 
orated (Fig. 67). In good weather this operation takes about 
eighteen to twenty-four hours but when cloudy or rainy, artificial 
heat must be used. Withering not only softens the leaves, but 
assists in the production of the greatest amount of enzyme which 
is needed in the later operation of fermentation. 




Fig. 68. — Rolling Tea Leaves. (Courtesy of The Tea and Coffee Trade Journal.) 

Rolling. — In China, rolling is still done very largely by hand 
(Fig. 68). The worker gathers a quantity of leaves in his hands 
and rolls and kneads the mass with a very similar motion to that 
used in the kneading of dough. In India the withered leaves 
are rolled almost entirely by machinery. This operation bruises 
the leaves, takes out excess moisture, and gives the characteristic 
twist to the leaf. 

Per mentation. — Fermentation is the most important part of the 



FOOD INDUSTRIES 26l 

preparation of black tea, for its influence on the quality and 
character of the tea is very great. The rolled leaves are piled 
in heaps on mats or frames and allowed to ferment until it turns 
a bright copper tint. During this period, the tea leaves are sub- 
jected to the influence of enzyme action and important chemical 
changes take place. The green color of the leaves and the dis- 
agreeable odor disappear, and a fine flavor due to the development 
of essential oils is acquired in proportion to the amount of enzyme 
in the leaf. According to the investigations of Dr. H. H. Mann 
"The tannin is oxidized during fermentation and combines with 
other substances in the leaf-forming compounds, some of which 
are insoluble in water; there is, therefore, a decrease in soluble 
tannin." Experienced judgment is necessary to determine how 
far fermentation should proceed; too little means rawness and if 
carried too far, much of the delicate flavor is lost. 

Firing. — Fermentation is checked by the application of heat. 
The leaves are sometimes exposed to the sun then fired or they 
may be immediately fired, care being taken that the temperature 
is sufficiently high to remove moisture, but not high enough to 
drive off the volatile oils which have been developed during 
curing. 

Sorting. — After cooling, tea is sorted into grades by sifting, 
is packed into lead-lined chests and is ready for transportation. 

GrFEn Tea. — The preparation of green tea differs from that 
of black tea in several important operations. 

I. The method of drying is different. While black tea is 
withered in the sun, the leaves for green tea in Japan are steamed 
until they lose their elasticity and in China are heated in pans 
over charcoal fires. In a few minutes the leaves become soft 
and pliable and are ready to be rolled. 

II. After rolling, the leaves are again subjected to the action 
of a slow, steady fire, the process of fermentation being omitted. 
The chlorophyl is, therefore, more or less retained and tannins 
are not oxidized to insoluble forms. This means that a larger 
amount of tannic acid is found in green tea when used as a 



262 FOOD INDUSTRIES 

beverage. The difference in flavor is entirely due to fermenta- 
tion. 

Adulteration. — In former years when tea was expensive and 
investigation slack, there was much fraud practiced, especially in 
the Chinese varieties. The adulteration consisted chiefly in the 
addition of foreign leaves and in facing. The leaves of the ash, 
beech, willow, rose and buckthorn were frequently mixed with 
those of the tea plant. Such substitution can readily be detected 
with the microscope as tea leaves have a characteristic appear- 
ance. Facing consisted in treating the leaves with various color- 
ing matter, such as Prussian blue, indigo or plumbago. By such 
means leaves which were inferior or had been damaged in manu- 
facturing processes or during a sea voyage, could be improved 
in color and general appearance. As black tea does not need 
as much care in preparation for the market, attempts were also 
made to face such tea and sell it for green tea. 

Since laws have been passed prohibiting the importation of 
faced tea, there is practically no adulteration to be found in the 
tea sold in the United States. Tea growers are more carefully 
watched, government inspection is more rigid and competition 
is much greater than in the past. For a lqng period the Chinese 
were the chief exporters to this country, but the rapid growth 
in the popularity of the India and Ceylon teas has forced China 
to send better grades to hold her place in the American market. 

Tea as a Beverage. — The main constituents of tea to be con- 
sidered in the preparation of the beverage are caffein and tannic 
acid. Caffein is the ingredient which gives the stimulating prop- 
erty. It belongs to a class of substances known as alkaloids. 

Caffein is not present in the leaf but is probably developed 
during fermentation. Just below the boiling point of water, it 
is remarkably soluble. Tannic acid is not particularly soluble at 
the boiling point, but will become so on prolonged boiling. These 
two facts must be taken into account when preparing the beverage. 
Caffein is a mild stimulant and is desired while tannic acid so 
far as possible should be avoided. 

General Kules for Tea-Making. — Heat freshly drawn water to 



FOOD INDUSTRIES 263 

the boiling point. Pour it on the requisite amount of tea, which 
has been placed in a previously scalded pot, made of a non-con- 
ducting material. Allow to stand in contact with the leaves from 
three to five minutes. The spent leaves should not be used again. 
Practically all the stimulating ingredient has been removed and 
that which is left is deleterious to health. 

Tea should never be boiled; the delicate aroma is lost as the - 
essential oils volatilize. Boiling also makes soluble the tannin, 
too much of which is undesirable. 

Composition of the Beverage. — Beside caffein, tannic acid and 
volatile oil, tea contains minute amounts of nitrogenous matter, 
fat, dextrin, fiber and mineral matter. 

COFFEE. 
^ Historical. — The early history of the cultivation of the coffee 
bean is lost in antiquity, but it is to Arabia that the civilized 
world is indebted for the knowledge of its use as a beverage. 
Tradition gives various tales of its introduction into Arabia, one 
of which places its original home in Abyssinia, province of Caffa, 
from which it is supposed to have received its name. The 
Ethiopians were known to have used coffee in very early ages, 
but with that nation it appears to have served as a food rather 
than a beverage. Wherever its origin may have been, Europeans 
discovered its use in Arabia during the 15th century. Undoubt- 
edly the knowledge of it spread very largely through the Arabian 
merchantmen, who added the coffee bean to other oriental lux- 
uries, and to the Mohammedan pilgrims who flocked annually to 
Mecca. Learning to drink coffee while in the "Sacred City," 
these pilgrims carried back with them, saddle-bags of the coffee 
bean to all parts of the globe professing the faith of Islam. 

It reached Constantinople in the 16th century and spread from 
there to the countries bordering on the Mediterranean, finally 
being introduced into London, Paris and other European cities 
during the 17th century. 

Originally all of the coffee used in Europe was grown in 
Arabia. As much of it passed through the port of Mocha, it was 
known under the name of Mocha coffee. Later coffee was grown 



264 FOOD INDUSTRIES 

in the European colonies, in the French West Indies and on the 
island of Java. Its cultivation soon spread to Sumatra, the 
Malay Archipelago, Ceylon, the Philippine and Hawaiian Islands 
and in the Western World to Cuba, Porto Rico, Mexico, and parts 
of Central and South America. About 1740 it was planted in 
Brazil where it gradually grew to be so important an industry, 
that at the present time Brazilian plantations produce three- 
quarters of the total supply and that government controls the 
coffee market of the world. 

The Coffee Plant. — The coffee plant is a very beautiful shrub 
attaining a native growth of some 18-20 feet, but under culti- 
vation, it is rarely allowed to exceed 4-6 feet in height. This 
dwarfing the plant, increases the crop and facilitates picking. 
The leaves are a fresh green color expanding outward and down- 




Fig. 69. — Coffee Bean. 

ward, giving a very pleasing appearance. The flowers occurring 
in clusters are white in color and have an odor strongly resem- 
bling jasmine. The flowers and fruit which are frequently called 
"the cherries" are found on the tree at the same time and in all 
seasons, in various stages of development. It is from these 
cherries which turn a dark crimson color on ripening, that the 
coffee bean is obtained. The outer part of the cherry is fleshy 
similar to other fruit, while within are two seeds, laid face to 
face, covered by a very delicate membrane known .as the "silver 
skin" and an outer straw colored husk called "the parchment" 
(Fig. 69). The main processes of manufacture consist in free- 
ing the fruit from the pulpy matter and removing the two inner 
skins which surround the seeds These seeds are in reality the 
unroasted coffee bean of commerce. 



FOOD INDUSTRIES 265 

Cultivation. — The coffee shrubs thrive best in rich, well-irri- 
gated soil and in tropical climate where the rainfall exceeds 75 
inches per annum. They are propagated from seeds, which are 
planted directly in the fields or grown in wicker baskets in nur- 
series until 18 inches high, when they are transferred to their 
permanent homes in the open. An absence of frost is essential 
to the growth of the plant and protection from wind and sun is 
commonly given by planting shade trees between the young coffee 
shrubs. The first crop of any importance is born when the plant 
is from 4 to 5 years old, and with care, harvesting may be con- 
tinued at regular seasons for 20 years or more. The fruit is 
ready to be picked when it is dark red in color strongly resemb- 
ling a ripe, red cherry. 

Processes of Manufacture. — Harvesting. — In Arabia, the fruit 
is allowed to remain on the tree until it falls off of its own 
accord, but on Brazilian plantations, which are by far the largest 
in the world, the cherries are usually picked by hand. They 
are allowed to fall directly on the ground or on sheets from which 
they are later raked together, and a first rough sorting is given 
before they are packed in bags to be removed to where further 
treatment is given. There a more careful sorting, sifting and 
winnowing take place, and the berries are at once treated with the 
dry or wet method for removal of the pulp. 

Dry Method. — The berries are spread out on drying grounds 
where they are left exposed to the sun for two or three weeks, 
during which time fermentation takes place and the pulpy mass 
gradually dries. It can then be removed by pounding in a mortar 
or by passing through a hulling machine. This method is still 
used in Arabia and to some extent on modern plantations of 
Brazil, many planters claiming that it has advantages over the 
modern wet process. 

Wet Method. — Where the wet proces's is used inclined canals 
are frequently built, where the cherries can be dumped and 
carried by gravity to the pulping machine. While floating down, 
imperfect and unripe berries rise to the top and can readily be 



266 



FOOD INDUSTRIES 



removed, after which the well developed berries are washed 
with fresh water (Fig. 70). 

Pulping. — The pulping machines are of various types, but as a 
rule they consist of a revolving cylinder with a rough surface 
which faces a curved metal plate. The berry is crushed between 
the two surfaces in such a manner that the pulp only is separated. 
The interior consisting of the coffee beans with the two coverings 
must not be injured. A separation is made by sifting and all im- 
perfectly pulped must be reprocessed. 




Fig. 70. — Views of Coffee Cultivation and Industry of Brazil. Washing Tanks. 
(Courtesy of The Spice Mill Publishing Co.) 



Fermentation. — The beans are next allowed to ferment for 
twenty-four to seventy-two hours in order to soften and loosen 
any adherent pulp. The essential part of this process is enzyme 
action on the adhesive substance, but as to its effect on the flavor 
of the coffee, no full investigation has as yet been made. 

Washing and Drying. — Successive rinsings with water finally 



FOOD INDUSTRIES 267 

leave the parchment covering quite free from adherent pulp. It 
is now known as "parchment coffee" and must be subjected to 
a drying process in order to remove the two inner coats by 
friction. Coffee is dried in most places out-of-doors, on the 
ground, during which time it is carefully watched. Too slow 
or too rapid drying greatly injures the flavor of the coffee. 

Peeling. — The two coverings can now be readily loosened by 
an ingenious machine which cracks the parchment and inner skin 
without injuring the beans. The hulls and dust are separated out 
by winnowing, leaving the coffee beans clean and ready for sort- 
ing. 

Sorting and Packing. — In order to secure uniformity, the beans 
are separated into six to eight grades. They are sorted first, 
according to size, by sifting through various mesh sieves ; second, 
according to weight by being subjected to strong currents of air 
blowing upward. The coffee is then bagged ready for removal 
to the shipping port, at which place it is frequently blended and 
repacked before shipment. 

As coffee deteriorates after roasting, that process is usually 
carried on in the country where it is to be consumed. On arrival 
at the -coffee-house, the raw bean is subjected to a thorough 
cleansing process to remove all foreign matter. 

Roasting. — The cleaned beans are run into a revolving oven 
and are subjected to a temperature of 200 C. In the production 
of a good coffee this is one of the most important steps. Count 
Rumford in an essay published in 1812 says — "Great care must be 
taken in roasting coffee, not to roast it too much; as soon as it 
has acquired a deep cinnamon color, it should be taken from the 
fire and cooled; otherwise much of its aromatic flavor will be 
dissipated and its taste will become disagreeably bitter. The 
progress of the operation and the moment most proper to put an 
end to it, may be judged and determined with great certainty; 
not only by the changes which take place in the color of the grain, 
but also by the peculiar fragrance which will first begin to be 
diffused by it when it is nearly roasted enough. This fragrance 
is certainly owing to the escape of a volatile, aromatic substance 



268 



FOOD INDUSTRIES 



which did not originally exist as such in the grain, but which is 
formed in the process of roasting it." 

When a light cinnamon brown is desired, coffee is allowed to 
remain in the oven for thirty minutes and from thirty-five to 
forty minutes, if a heavy chocolate color is wanted. It is then 
quickly cooled by blasts of cold air and is ready to be bagged or 
boxed for the market (Fig. 71). 

The effect of roasting is both physical and chemical. The 
physical state of the bean is changed to a brittle form, in which 




Fig. 71.— General View of Coffee Roasting Room. 
Publishing Co.) 



(Courtesy of The Spice Mill 



it can more easily be ground or pulverized. Two very important 
chemical changes also take place ; first, the formation of caramel 
which greatly improves the taste — this flavor can readily be 
imitated in the production of coffee substitutes ; second, the pro- 
duction of an oil known as caffeol to which the aroma of roasted 
coffee is due. As this oil is volatile, coffee should be consumed 
as quickly as posible after roasting and should never be pulver- 
ized until at the time of the preparation of the beverage. 

Adulteraton. — Adulteration of coffee has consisted in the ad- 



FOOD INDUSTRIES 269 

dition of foreign matter, the substitution of cheaper substances, 
and in facing. As with tea facing, the addition of coloring 
matter has been used largely to conceal poor or damaged coffee 
or to make inferior varieties appear as high grade material. In 
former years an imitation bean was manufactured and occasion- 
ally mixed with coffee, but the price of coffee is too low at 
present to make such substitution profitable. The addition of 
foreign substances was much more practiced with ground coffee 
than that sold in the bean form, since they could be less readily 
detected. Cereals of various kinds, peas, beans, acorns and the 
like have from time to time been added, but the chief adulterant 
has been found to be chicory which is the kiln dried root of the 
wild endive. 

In recent years misbranding has been found more frequently 
than adulteration. The early coffee market drew its supply 
almost entirely from Arabia and from the islands of Java and 
Sumatra. These coffees were known on the market as Mocha 
and Java. As the coffee industry spread, there was a strong 
tendency to label the product from new coffee fields as Mocha 
and Java, since those two names had taken a firm hold in the 
minds of the housewife.- The passing of the Food and Drug 
Act of June 30, 1906, has made this, also, a misdemeanor. Al- 
though undoubtedly much coffee is still on the market not prop- 
erly labeled, there is a strong tendency now on the part of the 
manufacturers, as well as the government, to have coffee imported 
under its own name. 

Coffee as a Beverage. — One of the most important constituents 
of coffee and the ingredient to which it owes its stimulating effect, 
is the alkaloid caffein. It is the same substance as is found in 
tea but occurs in a rather smaller proportion, approximately 1 
to 2 per cent, being found in the unroasted bean. Tannic acid 
is also found with a larger amount of other substances as fat, 
gum, fiber, sucrose, dextrin, reducing sugar and mineral matter. 
As coffee contains volatile oils, every effort should be made to 
retain them, in the preparation of the beverage, or much of 
the aroma and flavor will be lost. 



27O FOOD INDUSTRIES 

Coffee Extracts. — In recent years, products have been found 
on the market called coffee extracts. They consist essentially 
of a coffee solution from which the water has been evaporated 
in vacuo and the resulting mass, dried and ground. When 
added to boiling water, they are supposed to have the original 
consistency of coffee solution. 

COCO. 

Historical. — Coco was not known to the European nations until 
after the discovery of the Western World. On his return from 
the third voyage to America, Columbus was supposed to have 
carried back with him to Spain, the coco bean, as a curiosity from 
the newly discovered land. It was introduced into Europe in 
1528 by Cortez after his conquest of Mexico. The explorer 
found the natives of the new land using the roasted bean, ground 
and mixed with maize meal, moistened with the sweet juice of the 
maize stalk and flavored with vanilla and various spices. It was 
known to them as chocolatl and was considered to be highly 
nutritious as well as a beverage of great delicacy. Evidently 
it was also held in high esteem by the Europeans for the tree 
from which the fruit is obtained, was known to them as "Theo- 
broma, — food for the Gods." Although so highly prized, its 
use spread very gradually in Europe and it is not until recent 
years, that it has grown considerably in popularity. Possibly 
this is due to the fact that tea is used so extensively in the 
British Isles and coffee in the continental countries. Coco was 
first introduced into the States by the fishermen of Gloucester, 
and its use has increased to so great an extent that one-fifth of 
the world's crop is now consumed in the United States. 
v Cultivation. — Coco is the fruit of a tropical tree commonly 
known as the coco tree although it belongs botanically to the 
species cacao, the most commonly used being the variety theo- 
broma cacao. Thriving only in tropical climate, 20 both north 
and south of the equator, its cultivation is very limited. Only 
those localities of America and Africa with their neighboring 
islands, that have well-watered, well-drained soils and plenty of 
rainfall, can be utilized for the growing of the tree. The West- 



FOOD INDUSTRIES 



271 



ern World produces by far the largest part of the world's crop, 
Ecuador and Brazil being the largest exporting countries. 
Mexico still produces the greatest amount of coco, but uses most 
of it for her own consumption. 

\y The coco tree is grown from seeds either planted directly in 
the fields or in nurseries. It attains an average height of about 
20-30 feet and bears small, red, wax-like flowers which appear 
either singly or in clusters, along the trunk and main branches of 




Fig. 72.— Pods and L,eaves. 
(Copyrighted by Walter Baker & Co , and used with their permission.) 



the tree. The fruit is a pod some 8-10 inches long, 3-4 inches 
thick (Fig. 72). It is when ripe, either lemon color or chocolate 
brown, according to the variety, and has a thick tough rind en- 
closing a mass of cellular tissue. Embedded in the pulpy matrix 
are some forty or more coco beans which are covered with a 
thin shell greatly resembling an almond (Fig. y^). The beans 
are arranged in five longitudinal rows. The tree begins to bear 
fruit when four or five years old and continues to the age of 
forty. While blossoms and fruit are to be found on the tree, 
at the same time and in all seasons, there are two main crops 



2/2 



FOOD INDUSTRIES 



gathered yearly, generally in June and December, although this 
varies in different localities. 

Processes of Manufacture. — Picking. — The pods are picked, 
when fully ripe, either by hand or with a knife fastened to a 
long, bamboo pole. Great care is necessary, that the buds and 
blossoms which lie next the fruit are not injured. 

Decomposition of Pod. — As the rind of the pods when picked, 
is exceedingly woody and tough and would be difficult to cut, 
they are laid on the ground in heaps and allowed to decompose 
for twenty-four hours, or until the rind has become leathery. 
They are then sorted according to the degree of ripeness and 




Fig. 73. — Section Coco Fruit 

are cut open with a sharp cutlass. The pulp and coco beans, 
still within their shell, can readily be removed. 

Fermentation. — As a considerable amount of the soft pulp 
still clings to the beans, it is necessary in order to free them, to 
allow fermentation to take place. This process is carried out by 
heaping the beans on the floor where they are allowed to sweat, 
by burying them, or by the use of enclosed sweating boxes where 
they remain for several days. The seeds are frequently turned 
to insure regular sweating, great care being also given to keep 



FOOD INDUSTRIES 273 

the temperature from rising too high. Both alcoholic and acetic 
fermentation take place and several important changes occur. 
The germinating power of the seed is arrested; the adherent 
pulp is loosened ; color develops and an exceedingly bitter taste 
is modified so the flavor is greatly improved; the beans are less 
liable to be attacked by mold and are in the best form for dry- 
ing. 

Washing and Drying. — When fermentation is complete the 
beans are sometimes washed before drying. Washing is carried 
out by placing them in sieves or troughs, where they are thor- 
oughly scrubbed and rinsed, to remove all organic matter that 
may be clinging to them. Whether they are washed or not, the 
coco bean must pass through a drying process. This is accom- 
plished by the heat of the sun, whenever possible, or in drying 
houses which are heated by artificial means. In out-of-door 
drying some ten days or more are required, indoor drying is 
complete in less time. In some countries coloring matter is used 
and the practice of polishing the bean after drying is frequently 
performed. The coco is now ready to be bagged and shipped 
to the markets of the world. 

When received by the manufacturer coco is cleaned, sorted 
and roasted. 

Roasting. — As in the case of coffee, this process must be care- 
fully guarded to insure the development of the desired flavor; 
too much heat means bitterness and too little leaves the coco 
with a crude undeveloped taste. The process is usually carried 
out in large iron drums, heated to from I25°-I45° C. and con- 
stantly kept in motion. During the roasting the thin husks of 
the seeds become brittle and are so loosened, that afterwards they 
can easily be removed ; the aroma is increased ; the bitter taste 
is still further modified and the starch is partially dextrinized. 
When sufficiently roasted, coco is quickly cooled in order to 
prevent the loss of the aroma. 

Crushing. — The roasted seeds are next run through a machine 
called the cracker. This frees the outer shell from the inner 
parts which are known as coco nibs. A separation of shells, 



274 



FOOD INDUSTRIES 



nibs and germs is effected by sieves and a machine of special 
device. As the shells retain the flavor, they are sold and used 
for the preparation of a cheap beverage. The nutritive value is 
not great, but they make a satisfactory drink for people of weak 
digestion. The coco nibs are used for the preparation of the 
commercial chocolate and coco. 




Fig. 74. — Grinding Room. 
(Copyrighted by Walter Baker & Co., and used with their permission.) 

Preparation of Chocolate. — The coco nibs are ground into a 
paste by a series of revolving stones, arranged in pairs and 
slightly heated to assist in liquefying the coco. While in a semi- 
fluid condition, the paste is moulded into cakes and allowed to 
harden. It may be sold in this form as plain chocolate or the 
ground nibs may be passed into a mixer and finely ground sugar, 
spices, vanilla and other flavors may be incorporated. After 
moulding, it is placed on the market as sweet chocolate or as 



FOOD INDUSTRIES 275 

milk chocolate, if condensed or powdered milk has also been 
added. 

Preparation of Coco. — As the coco nib is too rich in fat for 
ordinary purposes, sometimes approximately one-half of the total 
weight, it is customary to remove a portion of it. The product 
is then known as coco. In the United States this is chiefly car- 
ried on by running the ground nibs, while in the semi-liquid 
form, directly from the grinder into an hydraulic press, which 
removes some 60-70 per cent, of the fat. It is then allowed to 
cool after which it is reduced to a powder and boxed. The ex- 
tracted fat is clarified and made into coco-butter. As coco-butter 
does not readily turn rancid if carefully stored, it is used largely 
in pharmacy, for candy-making and in the preparation of cos- 
metics, perfumes, pomades and soft toilet soaps. 

Adulteration. — Coco preparations have been much subject to 
adulteration. In order to increase the bulk and weight, sugar 
and various starches have been frequently added, while sand, 
clay, the ground shells of the coco-bean, powdered roasted 
acorns, chestnuts and other substances of organic and inorganic 
origin have, from time to time, been found. Fats of cheaper 
variety, as lard or coconut oil, are used to restore the normal 
percentage of fat after coco-butter has been removed. In 
cheaper grades of chocolate, glucose is sometimes used in place 
of sugar, while inferior flavorings and coloring matter are fre- 
quently added. 

As a Beverage. — Coco not only furnishes the material for a 
refreshing and exhilarating beverage, but is a food of great 
nutritive value. This may readily be seen by the average com- 
position of the coco bean as given by Payen. 

Fat 50 

Starch to 

Albuminoids 20 

Water • 12 

Cellulose 2 

Mineral matter 4 

Theobromine 2 

Theobromine which is responsible for the stimulating effect of 



276 FOOD INDUSTRIES 

coco, is closely related chemically to the alkaloid caffein, which 
occurs in tea and coffee and has a similar physiological effect. 
The presence of so high a percentage of fat, protein and car- 
bohydrate not only makes coco of greater nutritive value than 
tea or coffee, but both soluble and insoluble portions become a 
part of the beverage. This is not true of tea or coffee where 
only the constituents soluble in hot water are obtained. 

As chocolate is a concentrated food, it frequently causes 
biliousness when indulged in too freely. 



CHAPTER XXL 



SPICES AND CONDIMENTS. 

The word condiment is applied to products which possess no 
nutritive value, but are added to food to make it more palatable 
and to stimulate digestion. They may be either organic or in- 
organic. 

Sodium chloride or common salt, the most necessary to man 
and used to the largest extent, is inorganic. It appears to be the 
one item of food found in the diet of all nations and every race 
from the earliest times, the chlorine being utilized by the system 
in the formation of hydrochloric acid of the gastric juice, while 
the sodium is needed in the production of the bile. Its use is 
particularly important among people whose diet consists largely 
of vegetables and vegetable products. 

Salt is procured from natural deposits of sodium chloride in 
the form of solid crystals, from natural or artificial brine wells 
and from the sea by the process of evaporation. Formerly much 
of our salt came from the Bahama Islands. These islands are 
of coral origin and possess comparatively little vegetation. Small 
pools can be found in many places where the sun in time evap- 
orates the water, leaving a deposit of salt which could be sent to 
the market The product was known as Turks Island Brand. 
Natural brine wells are underground streams which may be the 
result of sweet water percolating through salt soil, or they may 
have come from a body of salt water. Artificial brine wells have 
been made by man by running water into a salt deposit. The 
brine may then be pumped to the surface which is an easier 
method of obtaining the salt than by digging. 

VA large part of the salt on the American market to-day comes 
from natural brine wells in the vicinity of Syracuse, New York, 
and along the borders of Lake Erie. They were discovered as 
early as 1654 by the French Jesuits, who found the Iroquois and 
other Indian tribes making use of the salt. Michigan in the 
southern part, Ohio and Kansas are also rich in saline deposits, 



278 FOOD INDUSTRIES 

and much is procured from Utah on the shores of Great Salt 
Lake. 

In the process of preparing salt for the market, the brine is 
passed through a succession of heaters with an increasing range 
of temperature. By this means many of the impurities are pre- 
cipitated and can be filtered off. The brine is then run into 
evaporators where the water volatilizes and the salt deposits. 
Since the salt still contains impurities it is purified by recrystalli- 
zation from water. It is then dried, sifted into grades and packed 
in bags, barrels or other packages. 

SPICES. 

Spices comprise all aromatic vegetable substances which may 
be added to food, principally to make it more palatable. They 
have been used from the earliest known eras of civilization and 
have played an important part in the discovery of a water pas- 
sage to the far east, in the colonizaton of the East Indies, and 
in the opening up of these countries to western civilization and 
to western trade. 

The tropical parts of Asia have given to the world by far the 
greatest variety and quantity of spices, such as pepper, cinna- 
mon, nutmeg, mace, cloves, turmeric, ginger and cassia. The 
tropical countries of America have added several new varieties to 
the list, as cayenne pepper and vanilla. The West Indies is 
celebrated for ginger and is also the home of the pimento. From 
Africa, grains of Paradise, are obtained. 

All spice plants are grown in tropical climates, latitude 25 ° N. 
and 25 S. of the equator, where there is considerable rainfall 
and soil with water absorbing properties. Most of these flavoring 
plants are found on islands in close proximity to the sea. Spices 
are obtained from different parts of the plant ; dried fruit as 
pepper, pimento, nutmeg, mace; dried bark as cinnamon and 
cassia ; flower buds as cloves ; the root as ginger ; seeds as cara- 
way ; leaves as sage, thyme, etc. Many of these owe their power 
to essential oils which in some cases are extracted and used as 
flavoring extracts. The flavor of others is due to esters and to 
alkaloids. 



FOOD INDUSTRIES 279 

Uses. — While the principal use of spices is to add flavor to 
food and beverages, this is by no means their only service to man. 
Many are used in perfumery, in soap making and in the manu- 
facture of incense. Several varieties are utilized in medicine 
chiefly to disguise a disagreeable flavor ; turmeric is used in 
dyeing and others in the various arts. In Egyptian days, they 
were utilized for embalming all the distinguished dead. 

While spices have been used from early ages in connection 
with food for the sake of the various flavors that they yield, 
it has been left to modern times to discover, that they also assist 
in the preservation of the material to which they have been 
added. This is due to the fact that they contain antiseptic prin- 
ciples. 

Spices as Preservatives. — That spices are useful as preservatives 
may readily be detected with such food products as sausages 
and mince meat. Mince meat as a rule, has for its chief con- 
stituents chopped meat and apples. Meat is subject to decay 
by bacterial action and apples furnish an excellent food for mold 
and yeast, yet it is a well known fact that mince meat will keep 
for many months. Sausage meat is subject to rapid putrefaction 
but in winter weather, it can also be kept for a length of time on 
account of the high content of spices. Fruit cake furnishes 
another example. It can be held for an indefinite period and 
even improves with age. Spices do not furnish a complete pro- 
tection, however, and food material to which they have been 
added should not be allowed to stand in a warm place, or fermen- 
tation and decay will set in. 

Although these facts have been common knowledge for many 
years, very little experimental work has been done, as to the 
varieties which contain the best antiseptic properties and the 
amount which should be used. Unfortunately many of them 
are irritating to the mucous membrane and when used in excess 
are harmful. It is very important, therefore, that the manu- 
facturer and housewife should know which spices may be used 
for their antiseptic properties and what the physiological effect 
is, of such condiments. To the experimental work of Conrad 
19 



280 FOOD INDUSTRIES 

Hoffman and Alice Evans, the authors are indebted for the fol- 
lowing information.* 

That ginger, black pepper and cayenne pepper do not prevent 
the growth of micro-organisms but that cinnamon, cloves and 
mustard are valuable preservatives. Nutmeg and allspice delay 
growth but cannot be considered of any practical importance, since 
the amount used in cooking is too small to preserve food for any 
length of time. Cinnamon, cloves and mustard are almost equal 
in their efficiency. Cloves when used in large enough amounts 
to prevent growth have a burning taste to the palate, but cinnamon 
and mustard are particularly valuable as they are palatable even 
when used in proportions that prevent all growth. The active 
antiseptic constituents of mustard, cinnamon and cloves are their 
aromatic or essential oils. Cinnamon contains cinnamic aldehyde 
which is more effective, if pure, than benzoate of soda. 
^ Commonly Used Spices. — Vanilla. — Vanilla is obtained from the 
fruit of a climbing orchid, native of tropical America, but now 
grown in Java, Ceylon and other parts of the Orient. It was used 
by the Aztecs as a flavoring agent for their favorite beverage 
chocolate, before the discovery of America, and was taken to 
Europe by the explorers as early as 1510. The fruit is a pod 
which must be dried and cured with great care in order to obtain 
the desired flavor. The characteristic odor is developed during 
the process of fermentation which takes place while drying. The 
aroma and flavor are due to a substance known as vanillin which 
gradually crystallizes out from the fluid of the pod. The well 
cured pods, either whole or powdered, may be found on the 
market as the vanilla bean or powder, but a more common form 
is the extract of vanilla. This is obtained by dissolving out the 
flavoring material by the use of alcohol. / 

Modern science has furnished a commercial rival to vanilla 
extract in the production of synthetic product. Vanillin has been 
largely prepared from engenol, a substance to which oil of cloves 
owes it characteristic odor, and in recent years much has also 
been obtained electrolytically from sugar. 

* The Use of Spices as Preservatives by Conrad Hoffman & Alice Evans. Published 
in Journal of Industrial & Engineering Chemistry. 



FOOD INDUSTRIES 



28l 



V Pepper. — Various spices can be found on the market under 
the general head of pepper, but the most common forms are black 
and white pepper. Pepper is one of the oldest spices known to 
mankind and is still used in enormous quantities. Although it now 
sells at so low a price that it may be utilized by comparatively 
poor people, it was worth its weight in gold during the days of 
the Roman Empire. The high price in the Middle Ages led the 
Portuguese to seek a water route to the far east, and the first 
vessel that sailed around the Cape of Good Hope had for its 
object the finding of a cheaper way to procure pepper. 




Fig- 75- — Pepper Plantation near Singapore. (Courtesy of The Spice Mill Publishing Co.) 



The black variety is prepared from the dried, unripe berry 
of a vine which was gr.own first in Southern India, the East 
Indies, Siam, Cochin China and in later ages in the West Indies. 
For a long period the Dutch nation controlled the trade and tried 
to confine its cultivation to the Island of Java and other Dutch 
possessions. 
■'The berry is gathered before it is fully matured, is spread out 
on mats for several days, after which the outer skin is removed 
by rubbing with the hand. It is then cleaned by sifting and is 



282 Food industries 

usually ground before being placed on the market. White pepper 
is generally supposed to be produced from a different spice but 
is in reality the same fruit, prepared by a different method. It 
is generally considered better but the product has not as good a 
flavor and is more expensive, the only advantage being in the 
appearance (Fig. 75)./ 

V Mustard. — The mustard most commonly used is obtained by 
grinding to a flour, the small seeds of the mustard plant. The 
plant which may be found either in the wild state or under cul- 
tivation has a wide distribution in Europe, northern Africa, 
Asia, the United States, the West Indies and South America. 
It has been used for medicinal purposes from remote antiquity, 
but appears to have been unknown as a condiment until 1829, 
when a resident of Durham, England, placed it upon the market, 
keeping the manufacturing process a secret. The product was 
given the name of Durham Mustard, a brand which is still 
found in the market of to-day.) 

The two most common varieties of seeds used at present are 
brown and yellow in color, the brown yielding the highest grade 
product. Mustard is prepared by passing the interior of the 
seed through a winnowing machine, for the removal of foreign 
material and crushing the grain between rollers, after which the 
oil is removed by hydraulic pressure. The cake is then dried, 
powdered and bottled. The powder is frequently mixed with 
spices and oil when it is known as prepared mustard. Much 
adulteration has been practiced in the preparation of mustard, 
principally in the addition of wheat flour, turmeric, cayenne 
pepper, etc. 

/ Cinnamon and Cassia. — Cinnamon is the inner bark of young 
shoots of a certain species of cinnamon tree, which is particularly 
rich in a volatile oil known as oil of cinnamon. It is apparently 
one of the oldest of the spices used by man and was the first 
sought after in the oriental voyages of the early merchantmen. 
The shoots are cut very carefully from the tree, the bark is slit 
longitudinally and is removed in strips by special knives. The 
strips are piled in heaps and allowed to ferment, after which the 



FOOD INDUSTRIES 



283 



epidermis is removed. The bark shrinks on drying and is known 
as "the quills." These are then put up in bundles ready for ex- 
portation (Fig. 76). 

Cassia in olden times was obtained entirely from the bark of 
other varieties of cinnamon trees. It was thick, comparatively 
coarse and was generally considered inferior to cinnamon. 
Much of the cassia of to-dav, however, is obtained from China 




Fig. 76.— Rolling Cinnamon Bark into Quills. (Courtesy of the Spice Mill Publishing Co.) 



and the Dutch West Indies, from the fragrant bark of a plant 
known as the cassia. It has a much more pronounced flavor than 
cinnamon and is frequently used as ah adulterant. 
v Cloves. — Cloves are the unopened flower buds of an exceed- 
ingly beautiful evergreen tree, which grows mainly in the Spice 
Islands. They were known to the ancients and were considered 
an important article of trade in the Middle Ages. The curing 
process is very simple. After picking, the buds are thrown on 



284 FOOD INDUSTRIES 

the ground on grass mats and are allowed to dry in the sun, care 




Fig. 77.— Clove Tree of Zanzibar. (Courtesy of The Spice Mill Publishing Co. ) 

being taken to shelter them from the dew at night. In about one 



FOOD INDUSTRIES 285 

week, they are ready to be packed for export. Cloves contain 
about 16 per cent, of a volatile oil, which can easily be removed 
and is of considerable value. It is used largely in perfumery and 
in soaps (Fig. 77)'. 

^ Allspice. — Allspice, known to the Spaniards as pimento, is the 
dried, unripe fruit of an evergreen tree native to the West Indies, 
Mexico and South America. The chief supply comes from 
Jamaica. The name allspice has been given on account of the 
fact that its very fragrant odor and flavor appears to be a com- 
bination of those obtained from cinnamon, cloves and nutmeg. 
The fruit is picked before it is ripe, is dried in the sun and 
usually ground on common burr-stones. It is used frequently 
for medicinal purposes to disguise the taste of nauseous drugs, 
and in the tanning of some kinds of leather. Allspice yields a 
volatile oil on distillation which is used as a flavoring in alcoholic 
solutions. * 

^ Nutmeg and Mace. — Nutmeg is the dried kernel of the fruit 
of a tropical tree somewhat resembling an orange tree. It is 
native to the Malay Archipelago, but is also grown largely in 
Asia, Africa, South America and the West Indies. The fruit is 
gathered when fully ripe and the outer part is discarded. The 
seeds are then dried in the sun or by artificial means. The thin 
outer seed coat is broken, and the kernal or nutmeg is ready to 
be cleaned and packed. Nutmeg is exported in the unground 
state in order to retain the flavor. The inner envelope which 
surrounds the nut is also dried, and exported under the name of 
mace. 

Ginger. — Ginger is the only spice taken from the root. The 
original home of the plant is supposed to be China, but it is now 
grown in many tropical countries. The West Indies produce an 
excellent quality, that from Jamaica usually being considered the 
best. The root may be left unpeeled when it is simply dried in 
the sun, or it may be peeled after having been scalded. Preserved 
ginger is prepared very largely in China, especially Canton. 
After being peeled, the ginger is treated with a boiling solution 



286 



FOOD INDUSTRIES 



of sugar, after which it is packed in jars or sent to the market 
in the dry state (Fig. 78). 

Adulteration. — In former years, no article connected with our 
food supply was more largely subject to adulteration than spices, 
especially when they were placed on the market in the ground 
condition. Spices of a good quality were usually high in price, 
and many cheap materials could be found which to some extent 
resembled the real article. They were used frequently as dil- 




Fig. 78.— Digging and Peeling Ginger in the Fields— Ginger Plantation, Jamaica. 
(Courtesy of The Spice Mill Publishing Co.) 



uents and to some extent as complete substitutes. According to 
Bulletin 13 of the United States Department of Agriculture, a 
profitable business for many years was carried on in manufactur- 
ing of products known as spice mixtures. They consisted of a 
combination of various materials as ground coconut shells, wheat 
flour, crackers, charcoal, coloring and mineral matter, yellow 
cornmeal, mustard, husks, sawdust and other odds and ends. 

Much misbranding has also been found especially among 
flavoring extracts. 



FOOD INDUSTRIES 287 

VINEGAR. 

Vinegar is used very largely in connection with food, the same 
as spices, to give flavor and as a preservative. Such articles as 
pickles depend largely upon vinegar for their keeping quality. 
It does not contain antiseptics as do the spices, but owes its pre- 
servative value to the acetic acid which inhibits the growth of 
putrefactive bacteria. 

The manufacture of vinegar has been treated under the Fer- 
mentation Industries. See Chapter XII. 



BIBLIOGRAPHY. 



CHAPTER L— FOOD PRINCIPLES. 
Sherman, Henry C. — Chemistry of Foods and Nutrition. 
Jordan, Whitman H. — Principles of Human Nutrition. 
Vulte, H. T.— Household Chemistry. 
Perkin and Kipping. — Organic Chemistry. 
Thorpe. — Dictionary of Applied Chemistry. 
Haas and Hill. — An Introduction to the Chemistry of Plant Products. 

CHAPTER II.— WATER. 
Mason, William P. — Our Water Supply. 
Richards and Woodman. — Air, Water and Food. 
Leffmann, Henry. — Examination of Water. 
Frankland, E. — Water Analysis. 
Wanklyn and Chapman. — Water Analysis. 
Harrington, Charles. — Practical Hygiene. 
Thorpe. — Dictionary of Applied Chemistry. 
Buchanan, E. D. and R. E. — Household Bacteriology. 
Schultz, Carl H. — Mineral Waters. 

CHAPTERS III AND IV.— OLD AND MODERN 
MILLING PROCESSES. 
,' Doudlinger, Peter Tracy.— The Book of Wheat. 
Edgar, William C. — Story of a Grain of Wheat. 
Amos, Percy A. — Processes of Flour Manufacture. 
Grant, James. — The Chemistry of Breadmaking. 
Wiley, Harvey W. — Foods and Their Adulteration. 
Bulletin No. 57, Agricultural Experiment Station, Ottawa, Canada. — 

Quality in Wheat. 
Trade Paper. — The Northwestern Miller. 
Encyclopedias. — Britannia, International. 

CHAPTERS V AND VI.— CEREALS AND BREAKFAST FOODS. 

Burtt-Davy, Joseph. — Maize : Its History, Cultivation, Handling and Uses. 

Freeman and Chandler. — The World's Commercial Products. 

Harrington, Charles. — Practical Hygiene. 

Wiley, Harvey W. — Foods and Their Adulteration. 

Ward, Artemus. — The Grocers Encyclopedia. 

Bulletin No. 131, Agricultural Experiment Station, Orono, Maine. — Indian 

Corn as Food for Man. 
Bulletin No. 118, Agricultural Experiment Station, Orono, Maine. — Cereal 

Foods. 



FOOD INDUSTRIES 289 

Bulletin No. 65, Agricultural Experiment Station, Orono, Maine. — Coffee 
Substitutes. 

Bulletin No. 211, State Agricultural College Experiment Station, Michi- 
gan. — Breakfast Foods. 

Bulletin No. 162, Dept. of Agriculture, Ontario Agricultural College, 
Ontario, Canada. — Breakfast Foods. 

Farmers Bulletin No. 249, U. S. Department of Agriculture, Washington, 
D. C. — Cereal Breakfast Foods. 

Farmers Bulletin No. 417, U. S. Department of Agriculture, Washington, 
D. C.^Rice Culture. 

Encyclopedias. — Britannia, International. 

CHAPTER VII.— UTILIZATION OF FLOUR. 
Jago, W. and W. C. — Technology of Breadmaking. 
Grant, James. — The Chemistry of Breadmaking. 
Buchanan, E. D. and R. E. — Household Bacteriology. 
Conn, H. W. — Bacteria, Yeasts and Molds in the Home. 
Jordan, E. O. — General Bacteriology. 
Farmers Bulletin No. 389, U. S. Department of Agriculture, Washington, 

D. C. — Bread and Breadmaking. 
The National Geographic Magazine, March, 1908. — Making Bread in 

Different Parts of the World. 

CHAPTER VIII.— LEAVENING AGENTS. 
Thorpe. — Dictionary of Applied Chemistry. 
Smith, Alexander. — General Inorganic Chemistry. 
Harrington, Charles. — Practical Hygiene. 
Bulletin No. 13, Part Fifth, U. S. Department of Agriculture, Division 

of Chemistry. — Baking Powders. 
Bulletin No. 52, Agricultural Experiment Station, Florida. — Baking 

Powders. 

CHAPTER IX.— STARCH AND ALLIED INDUSTRIES. 
Sadtler, Samuel. — Handbook of Industrial Organic Chemistry. 
Thorp, Frank H. — Outlines of Industrial Chemistry. 
Thorp. — Dictionary of Applied Chemistry. 
Olsen, John C. — Pure Foods. 
Humphrey, H. C. — Descriptive Paper — The Corn Products Refining 

Industry. 
Bulletin No. 202, U. S. Department of Agriculture, Washington, D. C. — 

Digestibility of Starch of Different Sorts as Affected by Cooking. 
Bulletin, Department of Agriculture, North Carolina. — Starches Used in 

Cotton Mills and Their Adulterations. 



29O FOOD INDUSTRIES 

CHAPTER X.— THE SUGAR INDUSTRY. 
Sadtler, Samuel P. — Handbook of Industrial Organic Chemistry. 
Thorp, Frank H. — Outlines of Industrial Chemistry. 
Thorpe. — Dictionary of Applied Chemistry. 
Wiley, Harvey W. — Foods and Their Adulteration. 
Durr, Noel. — Sugar and the Sugar Cane. 

International Library of Technology. — Manufacture of Sugar. 
The School of Mines Quarterly, Columbia University, April, 191 1. — The 

Chemistry of Raw Sugar Production; Sugar Refining. 
The School of Mines Quarterly, Columbia University, January, 1913. — 

Manufacture of Raw Sugar in the Philippine and Hawaiian Islands. 
The School of Mines Quarterly, Columbia University, July, 1913. — 

By-Products of Sugar Manufacture, and Methods for Their Utiliza- 
tion. 
Farmers Bulletin, No. 52, U. S. Department of Agriculture, Washington, 

D. C— The Sugar Beet. 
Report of the Eighth International Congress of Applied Chemistry, Vol. 

27-29. — The Status of Cane Sugar and Manufacture in the 

Hawaiian Islands. 
Trade Paper. — Sugar. 

CHAPTERS XI AND XII.— ALCOHOLIC BEVERAGES. 
Thorpe. — Dictionary of Applied Chemistry. 
Sadtler, Samuel. — Handbook of Industrial Organic Chemistry. 
Thorp, Frank H. — Outlines of Industrial Chemistry. 
Harrington, Charley. — Practical Hygiene. 
Accum, Frederick. — A Treatise of Adulteration of Food and Culinary 

Poisons. 
Buchanan, E. D. and R. E. — Household Bacteriology. 
Conn, H. W. — Bacteria, Yeasts and Molds in the Home. 
Fowler, G. J. — Bacteriological and Enzyme Chemistry. 
Osborn's Annual Guide, December, 1903. — Vintage and Production of 

Wines and Liquor. 
Bulletin No. 13, Part Third, U. S. Department of Agriculture, Division 

of Chemistry. — Fermented Alcoholic Beverages. 
Bulletin No. 239, Agricultural Experiment Station, Ottawa, Canada. 
Trade Paper. — The American Brewer. 

CHAPTER XIII.— FATS. 
Sadtler, Samuel P. — Handbook of Industrial Organic Chemistry. 
Thorp, Frank H. — Outlines of Industrial Chemistry. 
Thorpe. — Dictionary of Applied Chemistry. 
Wing, Henry W— Milk and Its Products. 



FOOD INDUSTRIES 29I 

Ward, Artemus. — The Grocers Encyclopedia. 

Leffmann and Beam. — Food Analysis. 

Wiley, Harvey W.— Foods and Their Adulterations. 

International Library of Technology. — Cottonseed Oil and Products. 

Bulletin No. 13, Part First, U. S. Department of Agriculture, Division 

of Chemistry. — Dairy Products. 
Bulletin No. 163, Agricultural Experiment Station, Fort Collins, Colo. — 

Farm Butter Making. 
Farmers Bulletin, No. 241, U. S. Department of Agriculture, Washington, 

D. C. — Butter Making on the Farm. 
Farmers Bulletin, No. 131, U. S. Department of Agriculture, Washington, 

D. C. — Household Tests for the Detection of Oleomargarine and 

Renovated Butter. 

CHAPTER XIV.— ANIMAL FOODS. 
Wiley, Harvey W. — Foods and Their Adulterations. 
Harrington, Charles. — Practical Hygiene. 
Hutchison, Robert. — Foods and Dietetics. 
Jordan, Whitman H. — Principles of Human Nutrition. 
Wilder, F. W. — The Modern Packing House. 
Ward, Artemus. — The Grocers Encyclopedia. 
The National Geographic Magazine, March, 1913. — Oysters : The World's 

Most Valuable Water Crop. 
Bulletin No. 114, U. S. Department of Agriculture, Bureau of Chemistry. — 

Meat Extracts and Similar Preparations. 
Farmers Bulletin, No. 391, U. S. Department of Agriculture, Washington, 

D. C. — Economical Use of Meat in the Home. 
Farmers Bulletin, No. 183, U. S. Department of Agriculture, Washington, 

D. C. — Meat on the Farm. 
Farmers Bulletin, No. 85, U.. S. Department of Agriculture, Washington, 

D. C. — Fish as Food. 
Farmers Bulletin, No. 128, U. S. Department of Agriculture, Washington, 

D. C. — Eggs and Their Uses as Food. 

CHAPTER XV.— THE PACKING. HOUSE. 
V Wilder, F. W. — The Modern Packing House. 

International Library of Technology. — Packing House Industries. 

The Chemical Engineer, December, 1906. — Chemical Engineering in the 

Packing House. 
Morris & Co. — The Pictorial History of a Steer. 
Wiley, Harvey W. — Foods and Their Adulteration. 



292 FOOD INDUSTRIES 

CHAPTER XVI.— MILK. 

Winslow, K. — The Production and Handling of Clean Milk. 

Rosenau, M. J. — The Milk Question. 

Wing, Henry H. — Milk and Its Products. 

Harrington, Charles. — Practical Hygiene. 

Buchanan, E. D. and R. E. — Household Bacteriology. 

Conn, H. W. — Agricultural Bacteriology. 

Conn, H. W. — Storrs Agricultural Experiment Station, Report 1895 — 
Bacteria in the Dairy. 

Leffmann and Beam. — Food Analysis. 

Bulletin No. 161, U. S. Department of Agriculture, Bureau of Animal 
Industry. — A Study of the Bacteria which Survive Pasteurization. 

Bulletin No. 104, U. S. Department of Agriculture, Bureau of Animal 
Industry. — Medical Milk Commission and the Production of Cer- 
tified Milk in the United States. 

Bulletin No. 107, U. S. Department of Agriculture, Bureau of Animal 
Industry. — The Extra Cost of Producing Clean Milk. 

Farmer's Bulletin, No. 363, U. S. Department of Agriculture, Washington. 
D. C— The Use of Milk as Food. 

CHAPTER XVII.— MILK PRODUCTS. 

Van Slyke and Publow. — The Science and Practice of Cheese-making. 

Wing, Henry H. — Milk and Its Products. 

Wiley, Harvey W. — Foods and Their Adulteration. 

Leffmann and Beam. — -Food Analysis. 

Luchsinger. — History of a Great Industry. Address at the State His- 
torical Society of Wisconsin. 

The National Geographic Magazine, December, 1910. — A North Holland 
Cheese Market. 

Bulletin No. 13, Part First, U. S. Department of Agriculture, Division 
of Chemistry. — Dairy Products. 

Bulletin No. 203, New York Agricultural Experiment Station, Geneva, 
New York. — A Study of Enzymes in Cheese. 

Bulletin No. 219, New York Agricultural Experiment Station, Geneva. 
New York. — Some of the Compounds Present in American Cheddar 
Cheese. 

Bulletin No. 236, New York Agricultural Experiment Station, Geneva, 
New York. — Conditions Affecting Chemical Changes in Cheese- 
making. 

Bulletin No. 237, New York Agricultural Experiment Station, Geneva, 
New York. — The Role of the Lactic Acid Bacteria in the Manu- 
facture and in the Early Stages of Ripening of Cheddar Cheese. 

Farmer's Bulletin, No. 487, U. S. Department of Agriculture, Washington, 
D. C. — Cheese and Its Economical Uses in the Diet. 



FOOD INDUSTRIES 293 

CHAPTERS XVIII AND XIX.— PRESERVATION OF FOODS. 

Appert, Nicholas. — The Art of Preserving All Kinds of Animal and Veg- 
etable Substances. . 

Duckwall, E. W. — Canning and Preserving. 

Thresh and Porter. — Preservatives in Food and Food Examination. 

Rideal, Samuel. — Disinfection and the Preservation of Foods. 

Wiley, Harvey W. — Foods and Their Adulteration. 

Green, Mary E. — Food Products of the World. 

Bulletin No. 1-3, Part Eighth, U. S. Department of Agriculture, Division 
of Chemistry. — Canned Vegetables. 

Bulletin No. 151, U. S. Department of Agriculture, Bureau of Chem- 
istry. — The Canning of Foods. 

Farmers Bulletin, No. 375, U. S. Department of Agriculture, Washington, 
D. C. — The Care of Food in the Home. 

Farmers Bulletin, No. 359, U. S. Department of Agriculture, Washington, 
D. C. — Canning Vegetables in the Home. 

Farmers Bulletin, No. 521, U. S. Department of Agriculture, Washington, 
D. C. — Canning Tomatoes at Home and in Club Work. 

Farmers Bulletin, No. 203, U. S. Department of Agriculture, Washington, 
D. C. — Canned Fruit, Preserves and Jellies. 

CHAPTER XX.— TEA, COFFEE AND COCO. 
V Freeman and Chandler. — The World's Commercial Products. 

Thorpe. — Dictionary of Applied Chemistry. 

Ward, Artemus. — The Grocers Encyclopedia. 

Harrington, Charles. — Practical Hygiene. 

Fowler, E. J. — Bacteriological and Enzyme Chemistry. 

Whymper, R. — Coco and Chocolate; Their Chemistry and Manufacture. 

Harris, W. B. — Paper on Coffee as Affected by the Food and Drug Act. 

Count Rumford. — Essay on The Excellent Qualities of Coffee and the 
Art of Making it in the Highest Perfection. 

Leffmann and Beam. — Food Analysis. 

Pan-American Union Bulletin, 1912. — The Cacao of the World. 

The National Geographic Magazine, October, 191 1.— A Visit to a Brazilian 
Coffee Plantation. 

Bulletin No. 13, Part Seventh, U. S. Department of Agriculture, Wash- 
ington, D. C. — Tea, Coffee and Coco Preparations. 

Farmers Bulletin, No. 301, U. S. Department of Agriculture, Washington, 
D. C. — Home Grown Tea. 

Trade Paper. — The Tea and Coffee Trade Journal, New York. 

\ 



294 FOOD INDUSTRIES 

CHAPTER XXL— SPICES AND CONDIMENTS. 
Ridley, Henry N. — Spices. 
V Gibbs, W. M. — Spices and How to Know Them. 

Freeman and Chandler. — The World's Commercial Products. 

Leffmann and Beam. — Food Analysis. 

Wiley, Harvey W. — Foods and Their Adulteration. 

Ward, Artemus. — The Grocer's Encyclopedia. 

Conn, H. W. — Bacteria, Yeasts and Molds in the Home. 

Hoffman and Evans. — Journal of Industrial and Engineering Chemistry. 

The Use of Spices as Preservatives. 
Bulletin No. 13, Part Second, U. S. Department of Agriculture, Division 

of Chemistry. — Spices and Condiments. 
Trade Paper. — The Spice Mill. Spice Mill Publishing Co., New York. 



INDEX 

PAGE 

Acetic ferment 98, 155, J 74 

Acid phosphate of lime 113 

Adulteration 59. 65, 71, 

73, 75, 81, 99, 152, 163, 170, 185, 195, 234, 254, 262, 268, 275, 286 

Albumins 12, 13, 148, 188, 190, 199, 212 

Albuminoids 13, 14 

Alcoholic beverages 153— J 75 

brewing 155-164 

champagne 169 

cider 173 

classification 153 

distilled liquor 171-173 

fermentation 154-155 

historical 153 

koumiss 175 

vinegar 174 

wine industry 165-171 

Alcoholic solubles 13, 14 

Ale 164 

Allspice 209, 280, 285 

Alum 26, 27, 32, 99, 109, 1 10 

Amino-acid '. . . . 13, 15, 230 

Animal foods 187-200 

beef extracts 191 

beef juices 192 

eggs 197 

fish 193 

internal organs 193 

meat 187 

shellfish 195 

Annatto 182, 245 

Ash (see Mineral matter). 

Bacteria 22-31, 87, 88, 

98, 99, 179-181, 196, 198, 213-224, 225-232, 233-239, 242, 247-251 

Baking powders 108-1 12 

alum phosphate 111 

ammonia 112 

phosphate no 

relative efficiency in 

tartrate : no 

20 



296 INDEX 



PAGE 

Barley 75, 76 

composition ". 75 

cultivation 75 

mill products 76 

origin 75 

uses 75 

Beef extracts 191, 208 

Beef j uices 192 

Beef viscera inspection 203 

Beer (see Brewing). 

Beet sugar factories 142 

Benzoate of soda 235, 244, 280 

Berkef eld filter 29 

Bicarbonate of soda 1 13-1 16 

Le Blanc method 114 

Solvay process 115 

Niagara process 116 

Biscuit industry 102-104 

Blood 206, 207 

Bolter 56 

Bolting reel 57 

Bonded whiskey 173 

Bone-black 113, 129, 149, 206 

Bone products 206 

Boracic acid 163, 209, 217, 235, 254 

Borax 32, 209, 217, 235. 254 

Brandy 171 

Breadmaking 84-102 

adulteration 99 

aerated bread 101 

leavened bread 87-91 

losses in fermentation 100, 101 

modern bread factory 95-98 

primitive methods 84-86 

souring and its prevention 98, 99 

steps in breadmaking 93-95 

yeast preparations 91 

Bread wrapping machine 100, 101 

Breakfast foods 77-82 

adulteration 81 

classification - 77-8i 

comparison of old and new 82 

Brewing 155-164 



INDEX 297 

PAGE 
Brewing {continued) 

adulteration 163 

composition of beer 163 

kinds of beer 164 

processes in manufacture 156-163 

raw material 155 

substitution 163 

Bromine 27 

Butter 177-182 

by-products 228, 229 

composition •. 177 

processes in manufacture , 178-182 

renovated 182 

substitutes '. 182, 204 

Butterine (see Oleomargarine). 

Buttermilk 228 

Butyric ferment 98, 212 

By-products 112, 113, 122, 150, 170, 201, 203-209, 228, 229 

Caff ein 262, 263, 269 

Calves brains 193 

Can closing machines 253 

Cane crushers 134 

Cane mill 133 

Canning industry 247-254 

adulteration 254 

containers 25 1 

historical 247 

meat products 251 

processes in manufacture 248 

success of canning 250 

Carbohydrates 7-1 1 

classification 8 

formation 8 

important properties 10 

occurrence 9 

Carbon dioxide 35, 90, 101, no, in, 154 

Carbonic acid gas generator 34 

Cardine 209 

Cassava ' 85, 118 

Cassia 282 

Caviar 197 

Cellulose 9 



298 INDEX 

PAGE 

Centrifuge 139 

Cereals 66-76 

adulteration 71 

barley 75, 76 

biological origin 66 

composition 67 

corn 67 

geographical distribution 66 

kinds 66 

oats 74, 75 

rice 71-74 

use in our country 66 

Cereal Department 63 

Champagne 169 

Cheese 229-234 

adulteration 234 

composition 230 

historical 229 

processes in manufacture 230-233 

uncured 233 

Chlorine 2"] 

Chocolate , 274 

Cholera 22, 27 

Cholera infantum 217 

Churning 181 

Cider 173 

Cinnamic aldehyde 280 

Cinnamon 209, 280, 282 

Citrate of lime 213 

Clotting 15 

Cloves 209, 280, 283 

Coagulated proteins 13, 15 

Coagulation 15 

Coal tar dyes 105, 182, 245, 254 

Cochineal 245, 254 

Cockle cylinder 53 

Coco 270-276 

adulteration 275 

as a beverage 275 

cultivation 270 

historical 270 

preparation of chocolate 274 

preparation of coco 275 



IND£X 299 

Coco (continued) page 

processes of manufacture 272 

Coffee 263-270 

adulteration 268 

as a beverage 269 

cultivation 265 

extracts 270 

historical 263 

processes of manufacture 265-268 

the coffee plant 264 

Coffee substitutes 82, 83 

Cold storage 199, 237, 238 

Collagen 187 

Coloring matter 182, 209, 232, 245, 246, 254, 275 

Condiments (see Spices). 

Copper boilers 160 

Copper sulphate 245, 254 

Corn (see Indian corn). 

Cornmeal 69 

Corn oil '. 125 

Corn syrup (see Glucose). 

Cottonseed oil 185, 186 

Crackers (see Biscuit industry). 

Cream of tartar 112, 113 

Cream separators 179, 180 

Creatin 192 

Creatinin 192 

Creosote 241, 242 

Crushers 123 

Curdling '. 15 

Dextrins 127, 128 

production of 127 

occurrence 10 

uses for 127 

Diastase 157, 158 

Diffusion battery 144-146 

Distillation 29, 172 

Domestic filters 28, 29 

Dough divider 98, 99 

Dough mixing machine 97 

Dripping boxes 126, 127 

Eggs 197-200 



300 INDEX 

Eggs {continued') page 

composition of the egg .-...- 199 

composition of the shell 198 

methods of preservation .• 198 

physical structure 197 

Elastin 187 

Emulsification 12 

Ensilage 150 

Extractives 15, 192 

Facing 262, 269 

Fats 1 1-13, 176-186 

butter 177-182 

butter substitutes 182-184 

composition 11 

cottonseed oil •. 185 

extraction 176 

occurrence 11 

olive oil 185 

peanut oil 186 

properties , 12 

purification 176 

utilization of .■ 204, 205 

Fertilizer 150, 186, 207 

Fermentation 88-90, 154, 161, 167, 260, 266, 272 

Filter bags 148 

Filter bed 24, 25, 26 

Filter plant 27 

Filter press 124, 125, 135, 146, 159, 162, 185, 186 

Fish 193-195 

adulteration 195 

edible portion 195 

nutritive value 195 

shellfish 19S 

Flour 44-6i 

adulteration 59 

bleaching of 59 

composition : 67 

entire wheat 61 

gluten 63 

Graham 60 

hard wheat 60 

milling of 44~59 

prepared 60 



INDEX 3OI 

Flour (continued) page 

soft wheat 60 

sifter and blender 96 

testing of 58 

Food principles 5—15 

Force 79 

Formaldehyde 217, 219, 235, 241 

Fructose 9 

Galactose 9 

Gelatin 187, 207 

Ginger '. 280, 285 

Globulin 13, 14, 212 

Glucose . .' 128, 129 

occurrence 9 

processes of manufacture 128, 129 

uses 128 

Glue 207 

Glutelins 13, 14 

Gluten feed 125 

Glycogen 8, 10, 188, 195 

Grape-Nuts 80 

Grape sugar (see Glucose). 

Hominy 69 

Hops 156, 160 

Hulled corn 68 

Hydraulic presses ' 124 

Hydrolysis 10 

Ice supply 31 

Indian corn 67-71 

composition 67 

earlj' cultivation 68 

early methods of preparation 68 

modern milling 69 

old milling methods 69 

origin 67 

uses 70 

varieties 68 

Invert sugar 11 

Jaggery 151 

Kidney 14, 193 



302 INDEX 

PAGE 
Koumiss 175 

Lactic ferment 98, 155, 180, 212, 231 

Lacto-chrome 213 

Lactose or milk sugar 9, 212, 228 

Lard 205, 234, 275 

Lardine (see Oleomargarine). 

Leavening agents 107-1 16 

acid phosphate of lime 113 

alum phosphate powders in 

ammonia powders 1 12 

baking powders 108 

bicarbonate of soda 113 

chemical agents 107 

cream of tartar 112 

early use of chemical agents 108 

phosphate powders no 

relative efficiency in 

tartaric acid 113 

tartrate powders no 

yeast 107 

Lecithin 200 

Liberwurst 193 

Lithia 32 

Liver 14, 193 

Logwood 245 

Macaroni 104-106 

Mace 285 

Maize (see Indian corn). 

Malic acid 165, 170 

Malting 156-159 

Maltose 9 

Massecuite 138 

Meat 187-191 

canning 208 

changes in cooking - 190 

chemical constitution 187 

extracts 19 1 

inspection 189 

internal organs 193 

physical structure 187 

reasons for cooking 190 



INDEX 303 

PAGE 

Medulline 209 

Menhaden , 68 

Meta-protein , 13, 15, 230 

Middlings 50, 54-56, 63 

Milk 21CK223 

certified 222 

composition 211 

diseases from 216 

importance of the supply 213 

modified 223 

necessity for cleanliness 217 

our duty to the producer 219 

pasteurization 222 

source 210 

sterilization 219 

testing 219 

Milk bottling machine 221 

Milk coolers 221 

Milk products 224-234 

artificially soured milk 229 

buttermilk 228 

cheese 229-234 

concentrated milk 227 

condensed milk 224 

dried casein 228 

evaporated milk 226 

milk powders 227 

milk sugar 228 

Milling 44-59 

advantages of new processes 57 

cleaning of wheat 52 

diagram of modern processes 50 

disadvantages of old processes 49 

grist mills 47 

hand-stones 44 

mortar and pestle 45 

quern 46 

reduction of the middlings 55 

roller mills 49, 53 

separation of the middlings 53 

tempering 53 

wheat blends 59 

Mill-pick 47 



304 INDEX 

PAGE 

Mineral matter 5, 6, 22, 

32, 70, 72, 74, 143, 150, 165, 188, 195, 198, 213, 230, 263 

Mineral waters 32-35 

artificial 35 

medicinal power 33 

natural springs 32," 33 

water, classification 32 

Mineral springs 33 

Molasses 136, 146, 151 

Molds 87, 88, 233, 235, 236, 239, 242 

Multiple-effect evaporating apparatus 137 

Musculine 209 

Mustard 280, 282 

Myosin 188, 190 

Neats-f oot oil 206 

Nucleo-protein , 14 

Nutmeg 280, 285 

Oats 74, 75 

adulteration 75 

composition 67, 74 

milling . . . < 75 

mill products 74 

Oatmeal : 74 

Oleomargarine 182-184, 204 

Olive oil 184, 185 

Open pan evaporators j 135 

Oysters 195-197 

Packing house 201-209 

beef extracts 208 

blood 206 

bone products ■ 206 

butterine 204 

canning of meats 208 

fertilizers 207 

gelatin 207 

glue 207 

growth and breadth of the industry 201 

hides, pelts and bristles 203 

historical 201 



INDSX 305 

PAGE 
Packing house (continued) 

inspection and slaughtering 202 

lard 205 

minor products 209 

neats-f oot oil 206 

tallow 204 

tankage 206 

sausages 208, 241 

Pancreas 14, i93> 209. 

Pancreatin 209 

Paragol 125 

Pasteurization 162, 220-222 

Peanut oil . . .' 186 

Pepper 209, 280, 281 

Pepsin 209 

Peptase 159 

Peptone 13, 15, 163, 230 

Phosphoprotein 14, 199 

Plumping 196 

Plastering 168 

Porter 164 

Preservation of foods 235-254 

alcohol 243 

canning 247-254 

cooling 237 

drying 235 

salting 239 

smoking 240 

sterilization 219, 247, 250 

sugaring 239 

use of fats and oils 242 

use of preservatives 243 

use of spices 243 

Preservatives '. 243-246 

Proteins 13-15 

classification 13 

composition 13 

occurrence 14 

properties 15 

Proteoses 13, 15 

Prussian blue 245, 262 

Puffed Rice 78 

Purifier 56 



306 INDEX 

PAGE 

Rennet 232 

Renovated butter 182 

Rice 71-74 

adulteration 73 

composition 67, 72 

cultivation 72 

geographical distribution 72 

milling 72 

origin 71 

uses 73 

Roller mills 53, 158 

Rum 171 

Rye 64-65 

adulteration 65 

composition 64, 67 

uses 64 

Saccharine 245, 254 

Saffron 105, 182, 245 

Salicylic acid 163, 174, 217, 235 

Salt 86, 181, 184, 233, 277 

Salting 239 

Samp 69 

Saponification 13 

Sarco-lactic acid 188 

Sausages 208, 241, 279 

Sauteing '... 191 

Scalper 53 

Scourer ' 53 

Scrapple 208 

Sedimentation basin 23 

Seminola 64 

Separators 52, 124 

Shellfish , 195-197 

Shorts 63 

Shredded Wheat Biscuit 80 

Smoking 240 

Sodium hypochlorite 27 

Sodium silicate 199 

Spices and condiments 277-287 

adulteration 286 

allspice 285 

as preservatives 279 



INDEX 307 

. PAGE 

Spices and condiments (continued) 

pnnamon and cassia , 282 

cloves 283 

ginger 285 

mustard 282 

nutmeg and mace 285 

pepper 209, 280, 281 

salt 277 

uses 279 

vanilla 280 

vinegar ; 174, 287 

Sterilization 219, 226, 247, 250 

Starch 1 17-129 

composition and formation 8 

corn starch industry 122-129 

occurrence 9 

outline of corn products industry , 121 

physical characteristics 117 

physical and chemical properties 117 

potato starch 118, 1 19 

source . of supply , 118 

tapioca 120, 121 

Stock boilers 249 

Strike pan 138 

' Stout 164 

Sucrose (see Sugar). 

Sugar 130-1S2 

adulteration ■ 152 

beet sugar industry 140-147 

block sugar 149 

cane sugar industry 132-140 

cane syrup 152 

comparison of cane and beet sugar 131 

date palm sugar 151 

history of the sugar beet 130 

history of the sugar cane 130 

maple sugar 151 

powdered sugar 132 

properties 132 

refining 147-149 

sorghum 151 

source 130 

utilization of the by-products 150 



308 index 

PAGE 
Sugar (ccrntinued) 

yellow sugar 150 

Sweetbreads 193 

Tallow 204 

Tannic acid .' 17c, 261, 262, 263, 269 

Tartaric acid 113, 165, 170 

Tea 255-263 

adulteration 262 

as a beverage 262 

classification 257 

composition 263 

culture of the plant 255 

green tea 261 

historical 255 

processes in manufacture 259-262 

rules for tea making 262 

Tea plant 256 

Theobromine 275 

Thymus gland 193, 209 

Thyroidine 209 

Tongue 193 

Tortillas 85 

Trachina 189 

Tripe 193 

Tuberculosis 189, 216 

Turmeric 245 

Typhoid fever 23, 196, 226 

Vacuum pan 136-139, 226 

Vanilla 280 

Vanillin 280 

Vinegar : 174, 175, 287 

Vodka 172 

Water 16-35 

atmospheric 18 

classification of natural water 16 

classification of potable water 18 

contamination of public supply 21 

contamination of wells 20 

danger of impure 22 

diseases from 22 



INDEX 309 

PAGE 

Water (continued) 

history of the water supply • 17 

ice supply 31 

importance of 7 

judging a supply 31 

mineral 32-35 

pollution of wells 20 

purification 23-30 

subsoil 19 

surface 19 

Water glass (see Sodium silicate). 

Wheat 36-64 

composition ■ 36, • 67 

cultivation 39 

geographical distribution t>7 

milling (old processes) 44~Si 

milling (new processes ) 52-59 

origin 36 

structure of the grain 41 

value of 42 

varieties 43 

Whiskey 172, 173 

Wild beet 140 

Wine 165-171 

adulteration > 170 

champagne 169 

composition 170 

improving wines 168 

preservation 171 

processes in manufacture 166-168 

sophisticated 170 

Wort 160 

Yeast 87-91, 154, 155 

Yeast preparations 91-93 

brewers , 91 

compressed 92 

dried ' 93 



